Using Red Light to Improve Metabolism & the Harmful Effects of LEDs | Dr. Glen Jeffery

Let's talk about indoor lighting >> because I am very concerned about the amount of short wavelength light that people are exposed to nowadays, especially kids.

>> This is an issue on the same level as asbestos.

>> This is a public health issue and it's big. And I think it's one of the reasons

big. And I think it's one of the reasons why I'm really happy to come here and talk because it's time to talk. When we

use LEDs, the light found in LEDs, when we use them, certainly when we use them on the retiny looking at mice, we can watch the mitochondria

gently go downhill. They're far less responsive. They their membrane

responsive. They their membrane potentials are coming down. The

mitochondria are not breathing very well. Can watch that in real time.

well. Can watch that in real time.

>> Welcome to the Huberman Lab podcast, where we discuss science and science-based tools for everyday life.

I'm Andrew Huberman and I'm a professor of neurobiology and opthalmology at Stanford School of Medicine. My guest

today is Dr. Glenn Jeffrey, a professor of neuroscience at University College London. In today's episode, we discuss

London. In today's episode, we discuss how you can use light, in particular red, near infrared, and infrared light to improve your health. And no, not just by getting sunlight, although we do talk

about sunlight. Dr. Dr. Jeffrey's lab

about sunlight. Dr. Dr. Jeffrey's lab has discovered that certain wavelengths or colors of light can be used to improve your skin, your eyesight, even your blood sugar regulation and metabolism. Dr. Jeffrey explains how

metabolism. Dr. Jeffrey explains how light is absorbed by the water in your mitochondria, the energy producing organels within your cells to allow them to function better by producing more

ATP. He also explains how longwavelength

ATP. He also explains how longwavelength light, things like red light, can be protective against mitochondrial damage caused by excessive exposure to things like LED bulbs and screens, which of

course we are all exposed to pretty much all day long nowadays. And simple,

inexpensive, and even zerocost ways that you can get longwavelength light exposure. And again, not just by getting

exposure. And again, not just by getting more sunlight. He explains that

more sunlight. He explains that longwavelength light can actually pass into and through your entire body and that it scatters when inside you. Now,

that might sound scary, but it's actually a great thing for your health because that's how long wavelength light can improve the health of all your organs by entering your body and supporting your mitochondria. Believe it

or not, certain wavelengths of light can actually pass through your skull into your brain and help promote brain health. During today's episode, we also

health. During today's episode, we also discuss new findings that correlate the amount of sunlight you're exposed to with longevity. Those are very

with longevity. Those are very surprising findings, but they're important. Also, why everyone needs some

important. Also, why everyone needs some UV light exposure. And we discuss whether it's important to close your eyes when using red light devices or in red light saunas and how best to apply red light and things like infrared light

in order to drive maximum health benefits. Today you're going to learn

benefits. Today you're going to learn from one of the greats in neuroscience as to how to use light to improve the health and longevity of any and every tissue in your body and the mechanisms

for how that works. Before we begin, I'd like to emphasize that this podcast is separate from my teaching and research roles at Stanford. It is however part of my desire and effort to bring zero cost to consumer information about science

and science related tools to the general public. In keeping with that theme,

public. In keeping with that theme, today's episode does include sponsors.

And now for my discussion with Dr. Glenn Jeffrey. Dr. Glenn Jeffrey, welcome.

Jeffrey. Dr. Glenn Jeffrey, welcome.

>> Thank you. Thank you very much.

>> We go way back. Later I'll tell a little bit of the story and why it is truly unforeseen that we'd be sitting here talking about what we're talking about.

But it's great to see you again and I'm super excited about the work you've been doing over the last few years because it's completely transformed the way that I think about light and health, light

and mitochondria. And frankly, every

and mitochondria. And frankly, every environment I go into now, indoor or outdoor, I think about how that lighting environment is impacting my cellular

health, maybe even my longevity. So, if

you would be willing, could you explain for people a little bit about light as, let's say, the visible spectrum, the stuff that we can see and the stuff that's kind of outside what we can see

as a framework for how that stuff impacts our cells. Because I think without that understanding, it's going to be a little bit mysterious how it is that lights of particular colors, wavelengths as we call them, could

impact our mitochondria the way they do.

But with just a little bit of understanding about light, I think uh people will get a lot more out of our conversation.

>> Yeah, sure. We think about light purely in terms of the light we see and that's that's perfectly natural. And the light we see runs from deep blue, violet out

to pretty deep red, deep bicycle light.

Um, and that's what we see. That's what

we're aware of. The trouble is that actually there's a lot more of it than that. The sun kicks out a vast amount of

that. The sun kicks out a vast amount of light that we don't see. So, let's say the visual range is just grab the numbers, which is say 400 to 700. That's

that's our spectrum.

>> Nanometers.

>> Yeah. Nanometers.

>> And there we're talking about the wavelength, how bumpy those wavelengths of light are.

>> Sunlight extends out almost to 3,000 nanometers. Just think about it. Big big

nanometers. Just think about it. Big big

range. And then that's in the infrared.

And on the other end, the bits that we don't see, the deep deep blues and the violets, that goes down deeply to about 300 nmters. Now, this is a continuum. We

300 nmters. Now, this is a continuum. We

parcel it up because there's bits we see and there's bits we don't see. You can

think about it as a continuous wavelength. And the wavelength gets

wavelength. And the wavelength gets longer and longer and longer as we go out into the deep red. So short

wavelength lights, the ones just below blue, they're very very high frequency.

They carry quite a kick. And that's why when you're sitting in the sun and you get sunburnt, it's mainly because of those ultraviolet short wavelengths that are present and then you go beyond our

visual range beyond 700 and the wavelengths become very very long and they carry a certain kind of energy but they don't carry the kick. So the

important point to think of is when you go out in sunlight, you see all these colors, blues, greens, reds, but there's so much out there that you don't see.

And we thought probably you didn't need to be aware of, but nearly all animals basically see this visual range that we have. Red, orange, yellow, green, blue,

have. Red, orange, yellow, green, blue, indigo, violet, right? We can separate those out by shining light through a prism. I think the cover of the Pink

prism. I think the cover of the Pink Floyd >> Pink Side of the Moon album. Um, and

that's separating out the different wavelengths. Um, you say that the short

wavelengths. Um, you say that the short wavelengths have a kick. Uh, I want to talk a little bit about what that kick is. Uh, we distinguish between ionizing

is. Uh, we distinguish between ionizing and nonionizing radiation. And I think for a lot of people, they hear the word radiation and they think radioactive and they think that all radiation is bad or

dangerous. But in fact, light energy is

dangerous. But in fact, light energy is radiating, right? So, it's radiation

radiating, right? So, it's radiation energy. But at the short wavelengths

energy. But at the short wavelengths below UV, >> they are ionizing radiation. And maybe

we could just explain what that means, how that actually changes our cells because if we get too much of that, it indeed can alter our DNA.

>> I think the important point to think about is not only what the wavelengths are, but also how body responds to those wavelengths. So let let's bounce back a

wavelengths. So let let's bounce back a little bit to for instance the sunburn.

Um we're getting sunburnt because the body is blocking those wavelengths.

those wavelengths cannot penetrate very far. So when you're out on the on a hot

far. So when you're out on the on a hot sunny day and part of your body goes pink, it's going pink because it's blocking those wavelengths. So the

energy is not being distributed throughout the body. The energy is hitting the skin and you're getting an inflammatory response to it. Now,

interestingly, we block those from our eye because our lens and our cornea also blocks those short wavelengths. So that's part of the

short wavelengths. So that's part of the reason why we don't see them. Um but

it's also the reason why for instance people get snow blindness because it's just sunburn on the cornea and the lens.

It's recoverable from but it's very painful >> and with age some people who get a lot of sun exposure will get cataract.

>> Yes. Yeah.

>> Which is a kind of a um the lens becomes more opaque.

>> It does. And I've heard that described as being the lens being cooked. Um, but

in actual fact, you know, I used to run uh the eye bank at Morfield's Eye Hospital, Eyes for Research, and you can actually open a patient's eyes up when they're dead. And you can look at the

they're dead. And you can look at the color of the lens, and you can get a rough idea of how old that person was.

>> So, one of the one of the surgical procedures that, you know, medics love is um to replace a cataract. take an

older person um they've got this thick brownish lens and pop it out and put a clear lens in and the instant response in 90% of them is wow in the patients.

Yeah. These are live patients.

>> They're live patients. It's done under a local anesthetic in in older patients.

They just go wow isn't that amazing?

Suddenly they're getting a lot more light in their eye.

>> Because the lens was brown it blocked a lot of the blu wavelengths and so they go everything is very bright.

everything's very sparkly. Um, and it it was it was quite a dramatic response.

But the interesting thing is two days later they said, "Yeah, it's gone."

>> And and the brain kind of reapts that visual input from from the retina.

Um, but going back over the literature of replacing cataracts, it's quite interesting. It tells you actually, you

interesting. It tells you actually, you know, quite a lot. Now when we put those plastic lenses in, we have UV blockers in them so that the amount of so you

don't actually get a lot of short wavelengths coming through. Um but there was certainly the response in the earlier days when we didn't have UV blockers of people saying, "God, that's

sparkly. That's really sparkly."

sparkly. That's really sparkly."

>> Yeah. The the sparkliness being those short wavelengths um like think of off the top of water on a really sunny day.

So, I think the takeaway for me is that we should all be protecting our skin against too much UV and other short wavelengths and we should probably

protect our eyes against too much ultraviolet exposure over time. We know

that you don't want the mutations of the skin that um or the the uh clouding of the of the lens. I mean, you pointed out you can replace the lens, but um you

know, I think at the same time, we need UV, right? I mean, vitamin D production

UV, right? I mean, vitamin D production is uh requires UV exposure. Um, do we know how what that how that works, what that pathway is?

>> Yeah, we've got a fairly good idea, but I want to just take you back a step if I may. There's some really fantastic work

may. There's some really fantastic work coming out at the moment where a few dermatologists are re-evaluating the issue of sunlight on the human body. And

the leader of that is um is a character called Richard Weller um from Edinburgh.

and he's going back over all the data and Richard's coming out and saying, you know, um all cause mortality is lower in people that get a lot of sunlight and

his argument is that the only thing you've got to avoid is sun burn.

>> You know, the mutations of DNA are occurring really when you've got very very high levels, not when you've got relatively low levels. And Richard's

work has been terribly interesting because he's dug out all the little corners, all the little things that you think about three days later. He's dug

out all those little corners. And you

know, things like uh aboriges in Australia don't get skin cancer. You

know, um white people there probably are in the wrong place given their evolutionary stage. But

evolutionary stage. But >> yeah, high levels of skin cancer in Australia, >> in the Caucasian population, >> but maybe they're getting too much sun exposure too fast. The UV index is very high down there. I will say you can I

mean you got you feel it quote unquote.

That's interesting. I hosted a uh a derm oncologist on this podcast Teao Dr. Teao Solommani. So he's a dermatologist who's

Solommani. So he's a dermatologist who's also an on dermcology. So skin cancer is his one of his specialties. And he um surprised me when he told us that um

indeed sunburn can lead to skin cancers.

Too many sunburns can lead to skin cancers. But that the most deadly skin

cancers. But that the most deadly skin cancers, the most deadly melanomas are not associated with sun exposure.

>> Those can occur independent of sun exposure and they often occur on parts of the body that get very little sun exposure. Like the melanomas will show

exposure. Like the melanomas will show up. I think Bob Marley died from uh

up. I think Bob Marley died from uh eventually from one that that started on his between his toes or something or on the bottom of the foot. There's a lot to unpack about the relationship between

light and skin cancers. And I'm I'm going to chase down the literature trail of this uh Weller guy.

>> Oh, Richard Weller is a Richard Weller is very interesting. He's he says I think he said he hasn't got any dermatological friends anymore.

>> Probably not.

>> But he also pointed out that um if skin cancer was directly related with sunlight, then we should find in skin cancer patients, you know, very high levels of vitamin D. In actual fact,

they've got relatively low levels of vitamin D. So, as you say, that story

vitamin D. So, as you say, that story needs to be unpacked. And what's

happened, I think, in the dermatological literature is that we've followed a pattern. Yeah. We've followed an

pattern. Yeah. We've followed an assumption and it's gone a very long way down the line and then it's taken a little bit of a rogue to come out and say, "Hang on, we need to take a step

back here." And I think Richard Weller

back here." And I think Richard Weller is leading that. And um um we we obviously both have an interest in daylight uh but his interest in daylight tends to be focused a little bit more on

those blue short wavelengths whereas I'm at the other end of the spectrum but uh I think he's a mover and a shaker.

>> Great. Well, I'm excited to see where that literature leads and I I'm glad that somebody's, you know, parsing, as you said, all the corners of it because I think we've been fed um a story that,

>> you know, excessive sunlight leads to skin cancer. And the data on all reduced

skin cancer. And the data on all reduced all cause mortality um in people that get a lot of sunlight. I I saw a study out of Sweden looks very very solid, but more data is needed clearly. Yeah. So,

>> I think that that story um there was a story out of Sweden. There was also a story out of the University of East Anglia and um we're talking big numbers, you know, we're talking very big numbers

on that. So it could have a lot of

on that. So it could have a lot of points that we don't quite understand yet, but I think the solid thrust of it and the interesting thrust of it for me is that that all caused mortality

flagships up on that are cardiovascular disease and cancers. It's not the obvious ones that we'd be thinking about. So yeah, let's use the term

about. So yeah, let's use the term unpacking. That one definitely needs

unpacking. That one definitely needs unpacking. But from a public health

unpacking. But from a public health perspective, that's an important area.

>> Well, I'm certainly a fan of people getting sunlight both in their eyes and on their skin. Although not to the point of burning, obviously.

>> Yeah.

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to change. For more information, please see the episode description. Today's

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to get up to $600 off. So, let's talk about um how light impacts mitochondria and other aspects of cellular function and maybe use that as a segue into the longer wavelengths.

>> Yeah, sure. that area is expanding enormously. Um, and it's expanding

enormously. Um, and it's expanding enormously in lots of little pockets and the pockets aren't weren't always talking to one another very well. Um,

the first person that came along and said, "Look, longer wavelengths are really positively affecting mitochondrial function

um was a lady called Tina Karu in Russia and who was very largely ignored. Um, I

don't I think she's still alive. I would

love to buy her a glass of champagne if only because she started it off. She

kick kickstarted it off. But she was very much of the opinion that mitochondria absorb long waves of light.

Parts of the mitochondria absorb it. And

one of my studies um to try and pin this down was to take a whole load of mitochondria, put them in a test tube, put a spectrometer on them and a light

and say, "What are these guys absorbing?" Well, I found the point

absorbing?" Well, I found the point where they were absorbing the damaging blue light, but I could not find the red. I could not find it. There was a

red. I could not find it. There was a lot of stomping around in the lab. You

know, who's made a mistake? You know,

everyone parceling the brain blame on.

But it changed. It changed because what absorbs long wavelength light?

Well, a most obvious one is water. The

sea is blue because the long wavelengths are absorbed. So someone came along and

are absorbed. So someone came along and said is it about water? Is it about water in mitochondria that's doing this?

Now when we make mitochondria make energy they make energy called ATP and you make your body weight in that every day. It's a vast process and you make it

day. It's a vast process and you make it as a wheel turns round. Mitochondria

have these little wheels these pumps that spin around but they spin around in water. Nano water. And apparently I'm

water. Nano water. And apparently I'm not a physicist. Nano water is viscous.

So one idea I think which we have to take quite seriously is that the viscosity of water is changing as a consequence of long wavelength light

that penetrates deeply in the body.

There is an increase in the spin rate of the motor that produces ATP and it gains momentum. Now that is absolutely fine. I

momentum. Now that is absolutely fine. I

can I can stick with that one. I think

that one makes considerable degree of sense and it gets us over a problem.

Mitochondria themselves are not absorbing long wavelength light.

>> It's the water that they're surrounded by.

>> It's it's their environment. Okay. So I

think in the end when you talk about the function of anything we tend to focus on that thing and we don't talk too much about where is it, what is it, what's it surrounded by and how does it influence

it. So the first reaction I think is

it. So the first reaction I think is that the motor starts to go around a little faster. But then something else

little faster. But then something else happens which is really interesting which is we start to make more of these chains that make energy. So let's say

mitochondria has got a is a chain. It's

a series of things and electrons are passed along that chain um to produce energy. Well when we give long

energy. Well when we give long wavelength light we find the proteins in those chains we find a lot more of them.

So my analogy is that giving red light gets the train to run down the track faster. That's true, but then something

faster. That's true, but then something detects the speed of that train and says, "Lay down more tracks. We need

more tracks."

>> So we're finding a lot more protein there um that is associated with passing that electron down the pathway to make energy.

>> Interesting. So it sounds as if longwavelength light via water is actually changing the structure of mitochondria and its function as well.

Yeah, I I think I I think I would say it's it's improving the function and it's influencing the the mito more mitochondrial proteins to be

synthesized. So we've got an immediate

synthesized. So we've got an immediate effect and we've got a longer term effect as well. Well, one thing we know about mitochondria is that they started off as independent bits of biology and

then the ukareotic cells which we have, you know, essentially took those in >> and they became fundamentally part of the the cell and it's passed on through the genome. So, the idea was that

the genome. So, the idea was that mitochondria were separate from our cells at one point or from cells and were were essentially um co-opted by our cells or hijacked our cells, we don't

know which. And then now they be because

know which. And then now they be because they share a genome, mitochondrial DNA and and genomic DNA, um they're passed along. And it makes perfect sense to me

along. And it makes perfect sense to me as to why that if they're really of bacterial origin, which we think they are, that they would be absorbing or through the water, they would be

absorbing long wavelength light because they evolved in water. I think it's worth us just uh mentioning uh this business of absorption versus reflection in terms of colors. I think people might

find this interesting that uh you said you know the ocean appears blue because it's absorbing all the red all the long wavelength light and it's reflecting back the short wavelength blue light.

>> Yeah. Yeah.

>> Red stuff does the exact opposite. Like

when we see a red apple it's doing the exact opposite. It's reflecting the red

exact opposite. It's reflecting the red light back towards us. The long

wavelength light. I think most people probably don't realize that. And then we talk about you know white containing all the wavelengths >> and black absorbing all the wavelengths right? That's that's the the notion. So

right? That's that's the the notion. So

it's it's it's interesting um to think about light as either being absorbed or reflected back and makes perfect sense to me why the mitochondria would absorb the red light. But of course I'm saying

that under already hearing the the just so story. So it makes sense once you

so story. So it makes sense once you hear it.

>> It makes sense when once you hear it and and why the hell did we not think about that five years ago? We know we were scientists make really big mistakes in

the pathways that they follow and you know they don't talk about their mistakes but their mistakes are every bit as important as their their great results. Why didn't we think about

results. Why didn't we think about water? Because our minds were trapped in

water? Because our minds were trapped in a certain pathway going down a certain alleyway. And so whatever you think

alleyway. And so whatever you think about the water hypothesis, the key point is that improvements in function as a consequence of exposure

to longer wavelengths light correlate tightly with what water absorbs. Right?

So okay, that's a big one. That that's a big one that is there. We know that's true. You can pull it apart and find

true. You can pull it apart and find there things called water holes where there are places where water absorbs a bit more than it does in other places.

But fundamentally the absorption of long wavelength light fits water.

So much of your work focuses on how long wavelength light can enhance the function of cells that are not on the surface of the body. They're not on the skin. They're in the eyes. And um and

skin. They're in the eyes. And um and now we'll get to these data soon, but uh you publish data that longwavelength light can penetrate very deeply and even through the body.

>> Mhm.

>> Even when people are wearing a t-shirt, like all the way through the body and impact mitochondria all along the way.

>> So maybe we should just talk about longwavelength light and how it can penetrate through the skin. You

mentioned that UV is is essentially blocked by the skin. So if I step outside for instance on a nice sunny morning or even a partially overcast morning but some long wavelength light

is coming through is it passing all the way through my body and impacting the water and mitochondria of every cell along the way? How is it scattering? I mean how

way? How is it scattering? I mean how how deep does this stuff go?

>> Okay, so let's stand you out. Let's

let's let's let's strip you off and stand you out in sunlight, you know, 12:00 in July.

The vast majority of longwavelength light is being absorbed in the body. So

what we assume is that it has a very very high scattering ratio. So the vast majority of that long wavelength light is going to hit inside your it's going to get through into your body and it's

going to bounce around.

>> So it's going to literally go through the skin.

>> It goes through the skin. And let's

let's take the simple experiment. The

simple experiment was you strip people off and you stand them in front of sunlight and you put a radiometer on their back.

>> Tell us what a radiometer radiometer measures the amount of energy coming through. Okay. And then we put a

through. Okay. And then we put a radiometer on we put a a spectrometer on your back as well which tells us the wavelength. So what we get from that the

wavelength. So what we get from that the reading we get from that is that a few% a few% is coming out the back. Now, we

shouldn't concentrate on that. What we

should concentrate on is what happens to the rest because it's not bouncing back from the surface of the skin. Very

little bounces back. It's being

absorbed.

>> Amazing. Which is amazing.

>> Well, it's very interesting.

>> It makes sense based on the physics of it, but but it's amazing, right? That

the long wavelength light is actually penetrating our skin, bouncing around in our internal organs, and some's getting out the other side. I think that's going to surprise a number of people. In any

conversation like this, we need to talk about silos, people coming from different angles at a problem. And I

have the advantage of uh Bob Fosbury working with me. Bob was um lead for analyzing atmospheres on exoplanets with the European Space Agency. He had a lot

to do with the European use of Hubble and a lot of his spectrometers are up on the James Webb telescope. Now, there are super advantages for having someone from another silo to come in, but there also

really annoying issues as well. So, I

said, "Bob, I really want to measure whether light goes through the body."

And he said, "We all know that. Forget

it. It's a waste of time, you know." And

I said, "You think you know it based on principles of physics. I don't know it."

And actually, I don't think you know something until it's published and everybody knows it and can talk about it. So, yeah, Bob came along and said,

it. So, yeah, Bob came along and said, "Yeah, it has to long wavelength." has

to go through. Um and um but it needed demonstrating. Now the other thing that

demonstrating. Now the other thing that I Bob did pick up on this and did start to get a lot more interested in it because then he went through his wardrobe and he took different layers of clothing from his wardrobe and put long

wavelength lights behind them. So what

goes through clothing? And the amazing thing is long wavelength light goes through clothing.

>> It goes through clothing.

>> It goes through >> any clothing.

>> Well, if you want to wear rubber, I think not. But if you want to wear um

think not. But if you want to wear um your standard t-shirt, I think I think he used six layers t-shirt.

>> And does color matter? Like I'm wearing a black shirt right now.

>> Makes no difference whatsoever. And the

other thing we do not know, and this is terribly important, there's lots of we don't knows here, is this long wavelength light bounces around all over the place. So we have got some long

the place. So we have got some long wavelength light sources. And I think I'm shining this long wavelength light there, right? And then when I put my

there, right? And then when I put my instrumentation up, it's all over the place >> inside the body.

>> Inside the body, inside the room, it's going every I can't control it. Not

unless I start putting materials like aluminium foil to block it. So when we think about long

it. So when we think about long wavelength, its advantages, you know, we talk about, you know, using this device or that device. What we also need to think about is uh okay, you've got a

small device with a small beam of light going here.

It's bouncing all around the room. It's

coming in from a different angle in different parts of your body, >> but certainly most concentrated in terms of energy at at the at the point source, >> but you cannot assume that the point

source is the only source of that long wavelength light if you're in a confined confined space. Well, let's um use that

confined space. Well, let's um use that as an opportunity to talk about a related study and then we'll circle back to the the uh let's call it the the light passing through the body study. Um

because the study I'm about to mention I think is going to be so interesting to people um and a little bit shocking >> and very very cool because it's

actionable. uh which is you did a study

actionable. uh which is you did a study showing that even if you illuminate just a small portion of the skin with long wavelength

light, it changes the blood glucose response, literally blood sugar response is altered by shining red light on the skin.

>> And for years there were these, let's call them um uh corners of the internet that would say things like, "Oh, you know, when you eat out of it, it has a different effect on your body than when you eat indoors." But there are too many

variables there, right? Because when you eat out ofdoors, typically it's at a picnic and then you have greenery and there's socializing and no one's going to fund a proper study to look at, you know, to parse every variable in a

picnic versus an indoor cafeteria and and it's not worth the taxpayer dollars, frankly. You did the right study, which

frankly. You did the right study, which was to shine light on what was it, the back.

>> It was on a small area of the back.

Yeah. And and I must make it very clear first of all, the person whose idea this was was my my colleague Mike Pner. And

um and Mike's thought processes were very very clear. We were on a long drive to do some research well out of London and that's a great time for cuz it's the the journey starts at 5 in the morning

that it's a great time for gossip. It's

a great time for wild ideas for streams of consciousness which sometimes are very important in science. And it was Mike who said to me, you know, if we

make mitochondria work harder, then they need glucose and they need oxygen. So,

pause while Glenn, who's driving, kind of has to catch up on this idea. I'm

generally about a mile behind him intellectually. And I went, "Yeah,

intellectually. And I went, "Yeah, yeah." So, he said, "Well, let's not

yeah." So, he said, "Well, let's not make idiots with ourselves. Let's do it with bumblebees."

with bumblebees." Right? So our first experiment was to to

Right? So our first experiment was to to increase of course why not the the why >> first experiment was on bumblebees because it didn't involve people. Um it

was simple to do and all we did was we starve bumblebees overnight. Gave them a standard blood glucose test. So you know lot >> sounds a lot harder than working on humans.

>> No it's not. You just give them a little bit of glucose cuz they haven't and they go and their blood glucose goes up.

you've gave them red light or blue light. We give them red light and their

light. We give them red light and their blood glucose does not go up as much. We

give them blue light and their blood glucose goes very high.

>> So, they're using more of the energy.

>> Yeah. So,

>> in the red light condition, >> in the red light condition, in the blue light condition, we're slowing their mitochondria down and so the uh there is more glucose flowing around. I should

say that sampling the blood in a bee is a little bit difficult, but um you basically pull off one of the antenna and you squeeze a bee and you get a little piece of

>> Well, the bee lover, but you know, we went to the chemist and we bought just the standard blood glucose test that you can get for a few dollars.

>> We got a result. Therefore, it's worth moving forward. Therefore, we got the

moving forward. Therefore, we got the ethical permission. Therefore, we did

ethical permission. Therefore, we did the exper I can't do the experiment on blue light. I regard that as unethical.

blue light. I regard that as unethical.

But really, yeah, >> we're under blue light all day. I'm

absolutely convinced that being under blue light or short wavelength shifted light all day is altering blood glucose in ways that are detrimental. But in any case, before I rant about that, what

what happened in humans?

>> So, in the humans, we did a standard blood glucose tolerance test, which is horrible. So, you get people to starve

horrible. So, you get people to starve overnight. They come in, they drink this

overnight. They come in, they drink this big sort of cup of vile glucose. So, we

really pump up the glucose in their body and then we prick their fingers at regular intervals and sample their blood and see how their blood glucose level

changes. And your blood glucose level

changes. And your blood glucose level will peak in about 40 to 60 minutes.

It's hard getting subjects for this one.

Um, we also put a tube up their nose so we could detect how much oxygen they were consuming. You're calling on

were consuming. You're calling on friends. I mean, I even dragged my son

friends. I mean, I even dragged my son in as a as a subject for that one. The

result when we gave people a burst of red light beforehand to stimulate their mitochondria was super clear. It wasn't ambiguous. The

super clear. It wasn't ambiguous. The

blood glucose levels went up, but they didn't peak anywhere near as seriously as they did without the red light. Now,

I'm told that the level of your blood glucose is not necessarily a massive issue for concern. What is an issue for concern is it spiking how much it spikes and the reduction in the spike was of

the order of it was just over 20% if I remember correctly.

>> Where was the light shown on the body?

>> It was shown on the back and it covered I forget what the percentage of the body area was. I did this calculation four or

area was. I did this calculation four or five times because it was ridiculously small. So we were stimulating a very

small. So we were stimulating a very limited area of the body but we got a systemic response. There was no way that

systemic response. There was no way that the mitochondria in that little patch of skin was having that effect. But it fits into a wider notion that all these mitochondria

act as a community. Now we now know that that's coming all from different corners. They act they do things

corners. They act they do things together. It takes them a little time to

together. It takes them a little time to have a conversation about it, but they act together. And if we're doing

act together. And if we're doing something which was over one to two hours, that's that's long enough for them to hold that conversation. I'd love

to know more about that. Do you recall whether the subjects could feel heat from the infrared light?

>> Okay. So, they're not they're not feeling heat. So, that removes also a

feeling heat. So, that removes also a potential placebo effect of some sort.

>> Do you recall just roughly uh what the area of illumination was? Was it you >> it's in the publication. Let's go like this.

>> Okay. So, for those just listening, maybe like a 4x6 rectangle.

>> Four 4x6 rectangle makes sense.

>> 4x6 in. Yeah. For the all those metric system folks out there, we're on common ground here given you're from the UK.

We're not unique in finding this. It's

just that other people are finding things with red light that are sitting behind different walls. So John

Metrofanes in you did most of his research in in Australia, he induces Parkinson's disease in primates, which you can do pretty much overnight with a drug and

and then he was giving red light to different parts of the body. Now

Parkinson's disease originates from a very small nucleus deep in the brain stem. Um but he was reducing the

stem. Um but he was reducing the symptoms of Parkinson's disease in these primates very significantly with lights that were being shown on the abdomen. So

any one of these you take in insul insul isolation and there are many of these studies and you go yeah maybe yeah >> what does he think it was doing? I mean

it's clearly it's not rescuing the dopamine neurons that degenerate in Parkinson's but maybe it's rescuing components of the pathway. it could be

rescuing components of the pathway. Um,

I think that we know that red light and we we we're using that term very loosely. Perhaps we shouldn't. We know

loosely. Perhaps we shouldn't. We know

that long wavelength light reduces the magnitude of cell death in the body.

Cell death is very often initiated apoptosis by mitochondria. When

mitochondria get fed up and that I see them as batteries when the charge on the battery goes down low enough they put their hand up and they say time to die >> and I think they actually present a molecular eat me signal.

>> Yes.

>> Which is interesting like you know when we talk about cells dying that we think about it as a um you know sort of they they go from a shout to a whimper and then they get cleaned up like they they

just they die but they actually um they solicit for their own death with this eat me signal. Yeah. they'll get

optionized you know for the people that you know think about the immune system optinization there similar things so if I understand correctly he induced an insult to these dopamine neurons and

then he used red light shined on the abdomen to offset some of the degeneration that would have occurred >> yeah okay now that that again fits into

the wider spectrum of other research that's not put together so that was John and John has been a big leader in uh red light dementia and Parkinson's disease.

Um, and a lot of it in primate models, which is which means it's it's got some it's got a lot of validity to it.

>> Yeah, they're similar to us to them.

>> Yeah. Another experiment we did was over life you will lose a third of your rod photo receptors in your retina.

>> Maybe just explain for people what the rod system is.

>> Okay. The rod system is the majority of your photo receptors are rods. They tend

they're the receptors that you use when you're dark adapted. Um, which a lot of us aren't really much these days. So,

we've got our cones which deal with color and deal with bright light. Then,

as we turn the lights down, we start to use our rods. So, loads and loads of rods, relatively few cones.

>> What I usually tell students is this is like you in the old days when everyone didn't have a smartphone near their bed.

You wake up in the middle of the night and you need to use the restroom. You

you can navigate to the restroom. You

might flick the light on in the restroom. I don't recommend doing that.

restroom. I don't recommend doing that.

It'll quash your melatonin unless it's a red light. Or you go out on a hike and

red light. Or you go out on a hike and you don't bring what we call a flashlight, Glenn. You guys call a

flashlight, Glenn. You guys call a torch. But as you come back, your your

torch. But as you come back, your your eyes start to adapt. It's it's getting dark. You can still see the outline of

dark. You can still see the outline of the trail. There's not starlight yet,

the trail. There's not starlight yet, but you you're able to, as you say, dark adapt and you can see enough of what you need to see. You're using your rod system.

>> Yeah. The key thing here is rods are me very very numerous. Cones are not. So,

so what what happens then for instance if we take a aging animals and we just expose them to red light every day we give them a burst of red light and then

we count the number of rods they've got when they reach old age and the result is super clear. We have reduced the pace

of cell death in the retina. Okay. So

red light is affecting mitochondria.

Mitochondria have the ability to signal cell death. And we're drawing back the

cell death. And we're drawing back the probability of that cell dying. Now, we

did that mice. We did it on a lot of mice. It was a killer of an experiment

mice. It was a killer of an experiment to keep animals going forever. And then

I forced one of my graduate students basically to go 1 2 3 4 and count photo receptor out the segments. She was a

hero. Um so we can use red light to

hero. Um so we can use red light to reduce the pace of cell death. So I am not too surprised that John Metrofanis

would have reduced the pace of cell death in the substantia Niagara that nucleus that gives rise to uh Parkinson's disease. Um I'm seeing that

Parkinson's disease. Um I'm seeing that coming out of loads of different labs things that are all consistent with that kind of story. The other thing that I think you can you can start to address

is if you've got bad mitochondria say very loose term if you've got bad mitochondria as you do have in uh Parkinson's disease you know they're bad

they're not functioning very well on their way to death are they influencing other parts of your body you know Parkinson's patients you think well okay they're all going to have movement disorders but actually a lot of

Parkinson's patients have a lot of other things that are going on in them And we're minded to think that as good information can be passed to

mitochondria and can be shared in that community, so can bad information.

>> You know, if you really upset mitochondria in one place, then other things are changing in different places.

So the big takeaway here, and it's not controversial to say, I've heard lots of people saying it, and I didn't say it originally, is that they're a community.

You can't deal with them in isolation.

>> Even across cells in different areas of the body, they're a community.

>> They are a community.

>> Probably by secretreting certain things that support each other. Um maybe I've heard some evidence that mitochondria can actually be released from cells.

>> Oh yeah.

>> Um >> different although not entirely different than neurotransmitters are released between cells and communi communicate between cells. very

interesting when one thinks about mitochondria of uh having maybe bacterial origin again that our cells co-opted or they co-opted us. We don't

know the again the direction there. Um I

have a question about how far long wavelength light can penetrate and through what tissues. I realized that in the studies we've been talking about it's long wavelength light exposure to the back lowering the blood glucose

response >> or to the abdomen offsetting some of the degeneration uh as it relates to this Parkinson's model.

>> If I were to take a long wavelength light and put it close to my head would it penetrate the skull?

>> Oh definitely. If you look at um if you if you look at a longwave light source and again this is published Bob Fosbury did this he put his hand on one come straight through his hand but the

interesting thing is you can't see the bones it's passing through the bone so that led me to go into grabbing a few

skulls and yeah it's it's really not affected that much by bone and I was talking to some aiology guys at uh in Cambridge who wanted to use red light

and they were they were taking I think heads or something and and looking at them and they were shining red light in the eye and they say we can see it in the ear that's not I can see it and vice

versa. So there are things that red

versa. So there are things that red light does not will not doesn't go through. So it is absorbed by

through. So it is absorbed by deoxxygenated blood. So you get

deoxxygenated blood. So you get fantastic pictures of your veins in your hand um or in your head. But the most obvious thing that you think is that long wavelength light would be blocked

by something thick like a skull. The

answer is no.

>> So going back to our example of the ocean appearing blue >> because of blue light getting reflected back and red light getting absorbed. I

think this is very important to kind double click on in people's minds because people will see an image for instance and I'll put a link to it in the from this recent publication of yours of red light and and other excuse

me long wavelength light not just red light um being shown on a hand and indeed you don't see the bones and you see the vasculature this deoxxygenated blood

>> when people see a structure under a particular wavelength of light the kind of reflex is to assume assume

that those structures are the ones that are um uh using the the the light, but in fact it's just the ex exact it's the stuff you don't see right that it's

passing through. And I think I think for

passing through. And I think I think for a lot of people that's just kind of counterintuitive. So they'll see an

counterintuitive. So they'll see an image of of the the veins during that deoxxygenated blood and they'll say, "Oh, you know, red light is is impacting the veins, right?" But but the interesting thing is that it's passing

through all that is interesting on in itself but it's passing through all these other structures and to me the idea that when I go out on a sunny day because the sun includes long wavelength light or were I to be near a long

wavelength light emmitting device >> that it's actually getting into the deep brain tissue through the skull for I think for most people it's just not intuitive to think about light passing through things that are solid in that

way.

>> Yes. And and I have exa I had exactly the same problem. I had exactly the same problem. Um if you you put a radiometer

problem. Um if you you put a radiometer and a spectrometer to measure the energy and the wavelength on one side of someone's head and a light source on the other side of someone's head, you you

get a clear result. Now, interestingly,

as a it's not a sideline, it's actually a very important issue. Um a a biomedical engineer Ilas Takanides at

UCL has used this because he works on some of his work is on neonates that have had stroke and he takes the neonate and actually does exactly that

experiment. He passes red light

experiment. He passes red light wavelengths of light through the side of the neonate's head and records them coming out the other side. and he can

use that as a metric of how well the mitochondria are functioning in that damaged brain. And the readouts that he

damaged brain. And the readouts that he gets are readouts that are indicative of the potential survival of that neonate.

Wow.

>> Now, I think there are lots of wows here. First of all, he's got his work

here. First of all, he's got his work into a major London teaching and research hospital. He's got it into

research hospital. He's got it into kids. And we've acknowledged that this

kids. And we've acknowledged that this is not dangerous, right? He's gone

through loads of ethics committees. The

long wavelength light red and out towards infrared and near infrared is nonionizing. Yeah.

nonionizing. Yeah.

>> Right. It's not altering the DNA of the cells. It's it's contributing to the

cells. It's it's contributing to the healthy function of the mitochondria.

Forgive me for interrupting. No, I think because when people hear about light passing through a baby's head, >> Yeah.

>> in order to make that kid healthier, I mean it's spectacular. I love that this is being done at at such a fine institution and so carefully. But the

reason it's safe is because that's long wavelength light. Were this to be short

wavelength light. Were this to be short wavelength light, we have no idea what it would be doing. I mean, babies have very thin skulls. UV would be who knows.

X-ray certainly you would never ever ever want to do this. So, yeah, I think it's important that people really remember what we're talking about passing through. Okay. And and I think

passing through. Okay. And and I think that it's a very important point because I have gone through so many ethics committees to shine long wavelength

light to do various things including on people that are they've got problems. So they've got they've got sight problems, their patients. We've actually also done

their patients. We've actually also done it with children. Um, and we've got through ethics committees really with very very little comment because on many of the ethics committees there are

physicists and they understand the issue.

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Let's talk about the two uh sort of bookends of uh age. You just mentioned uh babies and we'll return to uh babies, children, and youth. Uh let's talk about

some of the work you've done on retinal aging and using longwavelength light.

I'm being very careful with my language here because if I say red, people think you have to see it, but there's red, near infrared, nir it's typically shown as IR, infrared light. And I think we we

batch those when we say long wavelength light. It's going what 650 nmters would

light. It's going what 650 nmters would be red out to I guess is as far as 900 nmters or so.

>> And and yeah, and then beyond 900 is infrared. So we've got we've got the

infrared. So we've got we've got the near infrared and we've got the infrared. Now you're right, we've got to

infrared. Now you're right, we've got to start kind of we've got to start defining these terms a little bit more clearly. But I think for nearly all of

clearly. But I think for nearly all of the research we're talking about, we're talking about where vision stops, which is around 700, and we're talking about

the near infrared, which is for practical purposes is going up to around 900. Um, but you know, I I I remember

900. Um, but you know, I I I remember doing an experiment with um with UV once, and it was an experiment, bizarre experiment, trying to work out if a

reindeer could see UV light. Do they?

UV light. Do they?

>> Uh yeah, they do actually. But then, you know, while we were doing the experiment, I I was beginning to say, look, I I'm not believing any of this data because I can see this flashing now. And as was pointed out to me, you

now. And as was pointed out to me, you will see wavelengths of light, you know, that you shouldn't see if you just turn the energy up, >> right? So, if I put you in a room with

>> right? So, if I put you in a room with UV and I pump loads of energy into that UV, you'll see things that you shouldn't. And likewise with uh the

shouldn't. And likewise with uh the reds, you shouldn't really see much above 700. I can get you to see at 150

above 700. I can get you to see at 150 if I just turn turn the energy up a bit.

And you see these little red glows.

>> Yeah, this explains a lot of people's ideas about whether or not they've seen ghosts, but that's a different that's a different podcast, ghosts in UFOs. But

an interesting discussion for another time. But um and I can't help but

time. But um and I can't help but mention that, okay, maybe we'll return to this later, but Glenn has worked on a variety of species uh as have I over the years. So maybe at the end we'll do a

years. So maybe at the end we'll do a quick catalog of uh the species that we've worked on over the years. So I'm

not surprised to learn that you worked on rain reindeers given the other species you've worked on. But returning

to um the human you published some papers over the last uh you know five six years or so looking

at how when the eyes specifically are exposed to long wavelength light it can do excellent things for preserving vision or offsetting some uh loss of visual function. Could you detail those

visual function. Could you detail those experiments for us? So let's take two pieces of information first. So one of the main theories of aging is the

mitochondrial theory of aging.

Mitochondria regulate the pace of aging.

So if you can regulate mitochondrial health, you can regulate aging. That's

relatively clear. So that's that's the first thing. And then the second thing

first thing. And then the second thing to remember is that there's more mitochondria in your retina than there is in any other part of your body. Your

retina has got the highest metabolic rate in the body, ages fast, and my argument always is it's the sports car.

Bangs out of the garage, you know, but after after so many thousand miles, you got to service it otherwise it falls apart. So, there was a very strong

apart. So, there was a very strong argument for trying to manipulate mitochondria in the retina, which is great for me because I'm a retinal person. I'm a visual person, so I had

person. I'm a visual person, so I had the tools to do it. So the first experiment we did which was I very gratifying was to actually measure

people's ability to see colors. Now, we

used a rather sophisticated test first of all, and that was we'd put on a a very high resol resolution monitor, say the letter T in blue, and then we'd add

loads and loads of visual noise to it in the background or or we'd have a an F in red, visual noise, and then we found the threshold at which they could see that

letter and happily identify it. So, we

found out what their visual ability was for colors. We then gave them a burst of

for colors. We then gave them a burst of red light to improve their mitochondria in cells that are very mitochondrial dependent.

And we then brought them back and we found the threshold had changed. The

threshold had improved in every one of those subjects by one.

>> They could see something they couldn't see before.

>> See before >> by one. I think it's hard. Uh what what scale is it on? Like some of these tests like this is like the Triton test. Well,

so we tested Tritan and Proan.

>> So, this is nerd speak for the different visual tests. Um, most people are

visual tests. Um, most people are familiar with the Snellen chart. When

you go to get your driver's license, you have to read the letters of different sizes. Very different. This is measuring

sizes. Very different. This is measuring the just noticeable difference between you can see something, you can't see something. When you say there was an

something. When you say there was an improvement of but one, could you frame that in real world context for for people who are not thinking about visual psychophysics?

>> Okay. It's very simple. Of all the people we've tested, we've got an improvement and there's very large numbers of them except one subject.

>> Ah, you're saying but one. I thought you meant that was the numerical size of the the effect.

>> If you look over the population, the size of the effect is around 20%. It's

very substantial. Okay. But the our ability to improve visual function varies enormously between individuals.

You said but one. This is a UK uh US uh moment. No, but don't apologize. I

moment. No, but don't apologize. I

should apologize. Um okay. An

improvement of 20% improvement in threshold. So people are seeing better

threshold. So people are seeing better than they did prior. Could you explain what they did for them for the intervention? How how many times a week,

intervention? How how many times a week, a day? How long are they shining red

a day? How long are they shining red light in their eyes? What's the excuse me, long wavelength light? What what's

the nature of that light? Maybe even

tell us how far away from it they are.

>> Okay. So in our first experiments we used 670 nanometers right which is a deepish red light. The only reason we used that is because all the studies

before us doing different things had used 670. Consequently there was a

used 670. Consequently there was a database. So that's why we did it and we

database. So that's why we did it and we did it with a little torch that we put in front of somebody >> flashlight. That's trans I'll translate

>> flashlight. That's trans I'll translate for the flashlight. Not a torch with fire near the eye.

>> No definitely not. Um and um we did that for 3 minutes and originally we did that every day for an hour.

>> I open not not very little difference because the long wavelength light passes through the lid without it being affected very much. So I said to people, whatever you're comfortable with, you're

doing me a favor. You're being a subject in my experiment. I'm not paying you for it. You want to keep your eyes closed,

it. You want to keep your eyes closed, you keep your eyes closed. And those

people all had an improvement in their color vision. Now we then titrated that

color vision. Now we then titrated that down. So instead of doing it every day

down. So instead of doing it every day for so many days, we just did it for one day and 3 minutes of that light one day and we brought them back. I think it was

an hour later that it all improved.

>> How stable was the effect? I mean, did they have to only do one treatment ever?

>> No. Oh, I wish that was the case. In all

of those people, and I'd have to say we did it, we we've done similar experiments on flies, on mice, on humans. It's 5 days.

humans. It's 5 days.

>> It lasts 5 days.

>> 5 days. It's a solid 5day effect. So,

something very fundamental that is conserved across evolution is playing a role here. Five. And I have to say that to a first approximation,

anything I find in a fly, I find in a mouse. Anything I find in a mouse, I

mouse. Anything I find in a mouse, I find in a human. I can't find a a big disjuncture between those those things.

So, it lasted it lasted five days. And

the real big point to take on board is it's a switch. There's not a dose response curve here. It is a you put enough energy in at a certain wavelength

of light and it goes bang and click and then 5 days later goes chunk and stops.

I have a lot of questions about these studies. So, um I'm going to try and be

studies. So, um I'm going to try and be as precise about them. I know what's on people's minds. If people are going to

people's minds. If people are going to get in front of a long wavelength light emmitting device, do you think it's critical that it be

670 nmters or could it be 650 out to 800? I mean, how how narrow band does

800? I mean, how how narrow band does the does the light actually have to be in terms of wavelength? pretty much

anything works to a rather similar extent at 670 going upwards. When you go below 670 towards 650 the effects tend

to be somewhat reduced. If this is happening uh very quickly you said an hour later the vision is better thresholds have changed and it lasts 5 days.

Do you think we can get this same effect from sunlight given that sunlight contains these long wavelengths of light or is it that the the sunlight isn't of sufficient energy for most people? I

mean with this what you call torch I call flashlight light source you know you the way you described it and showed it with your hand for those listening is you know fairly close to the eye maybe you

know eyelids closed or maybe open if people can tolerate that and you're shining that light in their eyes for a couple of minutes.

How different is it than stepping outside on a really bright day closing my eyes if I look in the direction of the sun because that's pleasant or just walking in the sunlight and getting long wavelength exposure. I'm a big big fan

wavelength exposure. I'm a big big fan of natural sunlight because you've evolved life's evolved for billions of years under sunlight, right? It's only

recently changed. I don't know that cut off point, but there's an enormous difference between the light produced by a flashlight and sunlight. Sunlight is

an enormous broad spectrum >> and that flashlight is just a little window of light that happens also to be present in sunlight. Now, I think the

two situations are probably incomparable, >> right? And and I'm not going to spend

>> right? And and I'm not going to spend whatever is left of my career hunting that down.

>> We know and I I think this is the global concept I've got, which is that we can do much with single wavelengths of long wavelength light, right? Like a a

flashlight which is 850 or 610. We can

do a lot, but we can never do the same as you can get from sunlight. But you

can't do those tight controlled experiments with sunlight that I can do much more easily with specific wavelengths.

>> Yeah. And you're in the UK, so you'd have a lot of days to do experiments at all. I'm just kidding. Well, I must say,

all. I'm just kidding. Well, I must say, you know, often times when I tell people to get sunlight in their eyes in the morning to set their circadian rhythm.

I'm like a, you know, I'm like a repeating record with that and I will be till the day day I die. People will say there's no sunlight where I live. And I

remind them that even on a very overcast day, there's a lot of photon energy coming through, but the long wavelength light is cut is cut off. Um, so they're still getting a lot of photons. I mean,

compare how bright it is at 9:00 a.m. uh

versus midnight the night before their sun is that they can't see the outline of the sun as an object is what they're referring to.

>> I I think the important point there is that long wavelength light gets scattered by water. It gets absorbed and scattered by water. So on a winter's day

we've got a cloud and that cloud has got contains water. There will be an

contains water. There will be an attenuation of the longer wavelength light. It won't be vast but there will

light. It won't be vast but there will be an attenuation but more it will start coming at you in different angles. So

when you when you're walking on a sunny day and you're walking down the road, sun's in front of you, you feel warm in your chest when you've got clothes on and it's a longer wavelength light doing

it because it's relatively focused. on

that winter's day, you're still getting a lot of long wavelength light, but it's coming at you in a lot of different angles and it's slightly attenuated. So,

my argument, which is the new mantra of the of the lab to some extent, is get a dog, right? Get a dog because you'll

dog, right? Get a dog because you'll have to go out in you'll have to go out in daylight two or three times a day.

>> You'll get no argument from me. You

you're uh you're making me very happy.

Uh Glenn, uh I I love dogs. listeners of

this podcast will know I absolutely love dogs and my last dog it was an English bulldog half English bulldog half mastiff. So the next one will also be an

mastiff. So the next one will also be an English bulldog. Uh couple more

English bulldog. Uh couple more questions because I know people are curious about longwavelength light emmitting devices for their eyes and and other tissues. Um

other tissues. Um you mentioned that one subject did not respond and if I'm not mistaken these effects at least on the eyes I don't

know about the other effects on blood sugar etc but on the eyes and visual function seem to be gated by age right

if I recall people younger than 40 um you you saw less of a of an effect >> overall statistically we saw less of an effect you know some people.

My youngest son responded very very strongly and at the time I think he was about I think he was about 25. So you

have to look at a population level to get that but okay look this all makes sense. Mitochondrial theory of aging

sense. Mitochondrial theory of aging means that if we imp we we should have more room to improve mitochondria in the elderly than the young. But we all age

at different rates. One of the biggest problems about doing experiments on humans as opposed to mice is we all do radically different things. Some take

exercise, some have very good diets, some have poor diets. And mice sitting in our animal house eating the same food. They're very, very similar to one

food. They're very, very similar to one another. Everything is the same. So, we

another. Everything is the same. So, we

have to accept that noise. But generally

when your mitochondria are in a poor state which is consistent with aging, yes, we've got more room to lift them up and improve their function. What was the

time of day so-called circadian effect uh of this?

>> Very clear. Again, same in flies, mice, and humans. Your biggest effect is

and humans. Your biggest effect is always in the morning and it's always generally just before perceived sunrise

up until about 11:00.

So, and it's very very clear, but let's look at the backdrop to this. Your

mitochondria, they're not doing the same thing all the time. So, if we we we did this experiment 24 hours looking at mitochondria. And if you look at what

mitochondria. And if you look at what mitochondria are doing over 24 hours, it's shifting sh. not the same even over a 3-hour period. It's shifting and so

the the proteins that we have in different parts of mitochondria are changing in concentration radically.

It's it's a very very active area. So if

you're doing area if you're doing research on mitochondria and you're not taking account of time a day, you may have a problem. So but the mornings are

very very special. Um in the morning there are lots of things changing in your body. Your hormone levels are very,

your body. Your hormone levels are very, very different. Your blood sugars tend

very different. Your blood sugars tend to be picking up. You've been asleep. A

predator may have been watching you. You

need to wake up and you need to be ready on the road. You can't be like a lizard that's got to wait for the sun to rise and to get themselves into into a position where you can get your body

temperature up. So, the morning is very

temperature up. So, the morning is very important. You're making more ATP, this

important. You're making more ATP, this this petrol that mitochondria make in the morning than at any other time. Now

I can improve function across a wide range of issues in the morning. I can't

do it very easily in the afternoon. And

I think this comes from a very myopic point of view which is we think about mitochondria as purely as things that make energy. They do lots of other

make energy. They do lots of other things and and my interpretation is that in the afternoon well the standard lab joke is they're doing the ironing.

They're doing other things that as organels they need to do.

>> They are over a period of a day they're making contact with other organels in the cell particularly something called the endopplasmic reticulum. They're

junctioning with that. We've got such a limited view of what they do. I was

surprised to find that a mitochondria at 9:00 in the morning was not a mitochondria at 4:00 in the afternoon.

that poses some very serious problems about the interpretation of our data if people are doing things at different times of day.

>> So if somebody wants to improve their vision with long wavelength light exposure um maybe we can just give them a a rough contour of what this would

look like uh long wavelength of 670 and greater um emitting flashlight torch um at a comfortable

distance from the eye. So it could be, you know, 3 in, 6 in, a foot, depending on how bright it is. But if I were going to run the experiment, I'd probably want to bring it about as close as people

felt like they wanted to close their eyes, but then move it back just a little bit, just below the threshold of kind of I don't want to say discomfort, but where it's just too bright. And then

you're saying it doesn't matter if their eyelids are closed or open. You give it 3 minutes, 5 minutes of exposure once every 5 days or so. And is that going to

be sufficient?

>> There is the difference between something that has an effect >> and then the efficiency of that effect.

So if you take a 670 nanometer light source and you do exactly that, you will have an effect. Mhm.

>> Now, as we're going forward, we're finding certainly we're finding the energy at which you give that wavelength is dropping and dropping and dropping and still effective. So, you don't need

a very bright light.

>> No, no, you don't. So, we were the original uh experiments they used watts.

They measured it in watts, not lux. flux

is not very meaningful to this situation because it's it that's adjusted for the human eye. We want to know what was the

human eye. We want to know what was the energy that the cell experienced.

>> So people started off at say 40 mwatts per cime squared and I looked at that I thought criy >> that's bright >> that's bright >> that's very bright >> big after effect.

>> Yeah that's going to make someone wse >> it is. So then we got ourselves down to what we do in the lab now generally which is around eight which is very comfortable has the same effect.

>> Mhm.

>> But then we had someone in the lab do an experiment um and we had the flashlights that had batteries in them. She got a lovely effect and we found out the

batteries have been run down and she was getting an effect close at 1 mill per cm squared. That is low.

squared. That is low.

>> That's dim red light.

>> That is low. Okay. So, sounds like one can use dim to moderately bright red light that's comfortable. Um, I say red, but I mean long wavelength light that's

comfortable and likely get the effect.

Um, >> sounds like >> the effect can occur at any age, but it's going to be more pronounced in people that have experienced some loss of vision because of age, which everybody does.

>> Yes. You've also looked at this in the context of macular degeneration which is a very common form of blinding and especially in people as they get older.

Uh what were the results in terms of rescuing vision in people with macular degeneration?

>> Okay. So macular degeneration is when you could put it crudely that the center of your retina that you you're using for reading um degenerates and it's part of an you could say it's part of an aging

process. If I get you all to live to 50,

process. If I get you all to live to 50, uh say if I get you all to live to 100 years, probably 20% of you will have macular degeneration. It remember the

macular degeneration. It remember the retina as a sports car. It burns out. So

um I had a I had a very significant failure in a clinical trial because we took a whole group of patients um who had macular degeneration. We treated

them with red light and we treated their part more women have macular degeneration than men. We took their husbands as the control subjects. Um and

to a first approximation we got absolutely no effect whatsoever.

Uh this is kind of a point where you know people people working with Glenn are getting getting losing enthusiasm.

Um but lo and behold their husbands their vision they didn't have macular degeneration but their vision was improving enormously particularly the way in which they could deal with

darkness. So we we we stomped around

darkness. So we we we stomped around over this something was wrong and we found that when we looked back at it we found that the subjects that we were

dealing with the patients their disease had reached a certain point. It had gone beyond a certain point. Now when that study was replicated by someone who

thought about it a bit more than me, an opthalmologist called Ben Burton in the UK, he got a great result. He started to get a really good result. And when you talk to people about red light and I

talk to people, I talk to Parkinson societies, I talk to various groups and I talk to the researchers and it there is one thing that's very clear is that

red light can impact on aging. It can

impact on disease. But it can't do it if that disease has really got its teeth into you.

>> Right? So where we need to get into situations is early on in disease. So we

we thought very much about one point about rheumatism um you know rheumatoid arthritis.

>> Yeah. Very common autoimmune condition.

>> Yeah. And um we had absolutely zero effect. But all of the all the subjects

effect. But all of the all the subjects we dealt with already had hands that were quite twisted. It wasn't people coming in saying I've got this ache in my hand which is where we should have

intervened. So early intervention is

intervened. So early intervention is absolutely critical. We don't have to

absolutely critical. We don't have to give high energies. We don't have to give long exposures. We can improve situations but where we need to put our

effort is the efficacy of how we improve things. If I can improve something 20%

things. If I can improve something 20% well that's great for that person but can we improve it 80%. And that's all about wavelengths. It's all about

about wavelengths. It's all about energies. It's all about us thinking a

energies. It's all about us thinking a little bit more carefully before we set up the experiment.

>> It also makes me think that even though long wavelength light can penetrate the body and it scatters like for instance the shining of light on a 4x6 in

rectangle on the back impact blood glucose regulation everywhere. shining

long wavelength light into the eyes improved presumably mitochondrial function in order to increase uh the

visual detection ability um and on and on. Presumably the tissue that you focus

on. Presumably the tissue that you focus the light on if it's a focused light is going to derive the greatest benefit right or at least the most opportunity

for mitochondrial change. Then there

will there will be these systemic effects. Those mitochondria are talking

effects. Those mitochondria are talking other mitochondria. I mean, I'm

other mitochondria. I mean, I'm fascinated by how mitochondria are perhaps transported between cells and around the body. There's there's a not even a cottage industry anymore. I think

a lot of biologists are thinking about this seriously.

>> But let's say I want to improve the fun the mitochondrial function in in my gallbladder. Um, should I shine the red

gallbladder. Um, should I shine the red light on my gallbladder? It seems to stands to reason that that the answer would be yes.

>> I think the answer is yes. The issue is how quickly the effect takes place in distal and proximal tissues. So if you shine the light on your kneecap, something will probably happen within 1

to two hours >> at the kneecap.

>> At the kneecap, but then if you're examining the response of that um on your hand, it's 24 hours later, >> right? So the message has to get out and

>> right? So the message has to get out and things have to the story has to spread and the spreading of the story the spreading that's an intense kind of area

of of activity. What is the signal?

Where's it coming from? What is the signal?

>> And I think we we poked our finger at that slightly because we found that cytoine expression in the serum changed a lot.

>> Inflammatory cytoines are going down.

>> No. um increase in cytoine expression at low levels is protective.

>> Okay.

>> So what what it's saying to the body is brace yourself something's coming.

>> Immune system is getting mobilized.

>> Yeah. So um that was very very clear. So

animals that had improvements in physiology also had changes in cytoine expression.

>> I looked at that and I thought is that the real reason or is this a secondary, third or fourth level effect? Now, um

there's a there's some stunning stuff that I'm waiting to come out from, uh Westminster University in the UK, um being done, uh by uh a great scientist,

uh Ify, uh there. And what she's showing is a means of communication that we are very really rather unaware of, which is these micro vesicles that go around the

body, go around the serum. These

microvesicles carry cargos. Now they

carry all different sorts of caros and people have played with them a little bit in terms of changes in the gut microbiome. How does that affect the

microbiome. How does that affect the whole body? Um they've been talking

whole body? Um they've been talking about microvesicles and she's shown that microvesicle concentration is changing quite significantly with in fact what we

did with her was we didn't give her a red light we gave her an LED light where we change the LEDs in there to put some longwavelength elements in it. So the

communication around the body what is doing we've got to break that one what is it it's probably not one thing you know again scientists always think about one thing um it's a complex pattern when

I looked at the changes in cytoine expression my first reaction was I need a mathematician sitting next to me all these things are changing in a complex manner and I'm only looking at 50 of

them and there's probably over 300 so I could be missing the point but communication and you're right you know mitochondria Um, you can see cells come along to a

sick cell and they join together and the mitochondria is pushed in to the sick cell. How amazing. We'd have never

cell. How amazing. We'd have never thought about that.

>> Your mitochondria are ill. I'm going to come along and I'm going to give you some fresh mitochondria.

It's amaz they they the mitochondria are amazing and it's amazing how um little we really understand about how they work and yet what we do understand points to

how spectacularly important they are for energy longevity and as you pointed out how malleable they are. Yeah. Um and it all makes sense in the evolutionary

context of water and the absorption of red light. Another way that's kind of

red light. Another way that's kind of fun to illustrate this red light absorption by water thing is if uh anyone ever goes snorkeling what on a tropical reef, you'll notice that in the

first, you know, uh 10 ft of water from the surface down, you can see beautiful oranges and reds and um and then if you go deeper, those seem to disappear. They

haven't disappeared. It's just that the red light isn't penetrating that far, right? It gets absorbed. Yeah. uh if you

right? It gets absorbed. Yeah. uh if you bring a flashlight down with you as night divers do or even day divers will do that sometimes in order to see those those red fish are still there deeper um

but uh it disappears to you so it's very very interesting >> I'd like to take a quick break and acknowledge one of our sponsors function last year I became a function member

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like to um talk a little bit about the other end of the wavelength spectrum, shortwavelength light. And here I'd like

shortwavelength light. And here I'd like to move to artificial lighting um and point to what I think is a very serious concern. I I know it might seem a little

concern. I I know it might seem a little bit uh extreme, but I am very concerned about the fact that people are exposed to so much short wavelength, what's commonly referred to as blue light, but

I don't think that really captures it because people hear the words blue light and they think, oh, if a if a light source looks appears blue, then that

might be messing with my melatonin at night and might be messing with my mitochondria even. It's the white light

mitochondria even. It's the white light coming from LED sources, which are basically what we use as lighting sources nowadays, that yes, they contain

blue light, but they also contain, you know, violet light and stuff that doesn't appear blue because you've got the other wavelengths in there. In other words, white light

there. In other words, white light coming from LEDs is very short wavelength enriched.

To me, that's a problem. if short

wavelength light is causing dysfunction of mitochondria and I do believe that's the case unless it's balanced by the longer wavelengths >> and at the same time like anything it

can be remedied if we do the right thing. So could you illustrate for us

thing. So could you illustrate for us what what happened over the last you know 30 years or so in most every country as we moved from in uh well actually let's take it further back.

Let's go from fire candle light and fire light to incandescent bulbs.

Let's also talk about hallogen bulbs and now LED bulbs. I know people like to focus on screens, but we'll set aside screens for the moment. Let's talk about indoor lighting

>> because I am very concerned about the amount of shortwavelength light that people are exposed to nowadays, especially kids, >> especially given what you told us about blood glucose regulation.

What's known about this? Okay, this is this there's a group of us shuffling around corridors all mumbling to one

another saying, "How big a stink is this?" And some people are I I reviewed

this?" And some people are I I reviewed a document that was sent to the European Commission last week just before I came over here from a very

balanced uh Dutch lighting engineer when he wrote to the European Commission saying, "We've got to rethink this." And

so the group of us that are shuffling around, some of them are saying this is an issue on the same level as asbestos.

This is a public health issue and it's big. And I think it's one of the reasons

big. And I think it's one of the reasons why I'm really happy to come here and talk because it's time to talk, right?

We we've got enough data. So LEDs came in and people won the Nobel Prize for this very rightly at the time because

they save a lot of energy. They are very energyefficient because they do not produce on the whole light that we do

not see. So the effort is all in what we

not see. So the effort is all in what we see. Now, as you pointed out, the LED

see. Now, as you pointed out, the LED has got a big blue spike in it, although we tend not to see that. And that is even true of warm LEDs, and there is no

red. Remember? So, we're talking about

red. Remember? So, we're talking about billions of years of evolution under broadspectctrum sunlight. When we had

broadspectctrum sunlight. When we had fires, that was pretty much the same. A

fire is pretty much broadspectctrum.

Candles, pretty much broadspectctrum. So

nothing really changed in our world until around 2000. As we get to 2005, we're starting to find that the incandescent lights with their loads of

infrared start being pushed off the market.

>> And that was purely because they they take more energy. Electric bills are higher and they don't last as long.

>> Yeah. Exactly. So, um, when we use LEDs, the light found in LEDs, when we use them, certainly we use them on on the retiny looking at mice, we can watch the

mitochondria gently go downhill. They're far less responsive. They their membrane

responsive. They their membrane potentials are coming down. The

mitochondria are not breathing very well. Can watch that in real time

well. Can watch that in real time >> under LED lighting. and LED lighting at the same energy levels that we that we would find in a domestic or or a commercial environment.

>> That's very concerning to me. I

>> it is it was never picked up. Then also

if you do experiments say for instance on flies, flies don't live as long under blue light, right? Their mitochondria

again decline quite marketkedly. You

produce less ATP.

Um, if you look at mice, you find mice put start putting on a lot of weight.

They start putting on a lot of weight because their mitochondria are not taking that glucose out and it's being deposited as fat. Their control of their blood glucose, not surprisingly, becomes

unbalanced and they start to behave slightly peculiarly in open field situations. Now, you and I know that

situations. Now, you and I know that when you put a mouse in an open field situation, uh, it's a measure of how confident it feels. So, it runs around the edge at the first until it feels

happy and then it wanders around the middle and the rest of it. Mice under

LED lighting do not make that transition from working around the edge and coming into the center. And that is possibly consistent with the notion they have

lowle infection, chronic infection.

That's all published. Now, there's some stunning data coming out of another lab.

It will come out early next year, showing that these same mice have fatty livers. Again, not really desperately surprising. So, same food

desperately surprising. So, same food chow as their as their full spectrum light counterparts, but they're under LED lighting and they've got fat fatty

li but there's a a clear systemic effect here because their livers are smaller, their kidneys are smaller and their hearts are slightly smaller. With the

liver problems, we get a raise in what we'll call um liver distress signals, proteins coming around. one that's

called ALT which tells you your liver is not happy at all. Interestingly um where do you also find vast numbers of mitochondria? You find them in sperm. So

mitochondria? You find them in sperm. So

there is a greater concentration of sperm with abnormal swimming capacity and abnormal morphology in those mice and the testicles have abnormal

morphologies. Now these are animals that

morphologies. Now these are animals that are really run towards the end of their life. Okay. But again, let's put all

life. Okay. But again, let's put all these things together. This is clearly telling us that it's not just the LED.

It's the LED range which is 420 to 440.

It's a specific range that the mitochondria absorb and it's the absence of the red light to counterbalance that.

Got it. So, this is so important for people to hear. U and I just want to reiterate something you said earlier.

You said that at least to your mind this exposure to excessive amounts of shortwavelength light because of LEDs is possibly

as serious as asbestos exposure in terms of its um detrimental effects to human biology. Possibly. Possibly. That's what

biology. Possibly. Possibly. That's what

we're shuffling around saying getting confident about it. Um I point out another issue now. Now my some you know your colleagues some are a bit more excitable than others. Some of them are very conservative and citizen.

>> Depends on how much red light they're getting.

>> Bad joke, I know.

>> Yeah, bad joke. Um, let's look at um growth in lifespan in Western Europe chugs up. Chugs up chung slowly. You

chugs up. Chugs up chung slowly. You

know, we're living slightly longer on average one year than the next. Um, and

really, you could draw a line along that that curve. Yeah, it's relatively

that curve. Yeah, it's relatively straight.

We get a dent in the curve and the tendency towards asimtote which means flattening out after about 2010.

Now that can be corrected for co something is turning that down. Now, I'm

not going to say LEDs are shortening lifespan, but I've got a number of colleagues around me who are saying you need to take this one into account.

>> And you did say earlier that amount of sunlight exposure um which includes balanced wavelengths of short, medium, and long wavelengths is associated with um longer life, less all cause mortality.

>> Yes, definitely.

>> And that brings me to the other point that uh you made. So, I'm just I'm aware that I'm just restating what you said, but it just it's really hovering in my mind as so important that we I think people need to hear it again, which is

it may not be that short wavelength light is detrimental to mitochondria per se. It's that in the absence of

per se. It's that in the absence of balanced light, you're you're taking whatever mechanisms that short wavelength light have on mitochondria and you're you're tipping the seesaw in that direction and the other side of the

seessaw would be weighted by long wavelength light. So presumably because

wavelength light. So presumably because mitochondria evolved under short, medium, and long wavelength light. I

mean, let's be fair. It's not like they evolved under red torches as you call them, right? Um the the balance between

them, right? Um the the balance between these wavelengths is really what's key.

And LEDs are just shifting the balance very heavily to short wavelengths. So I

realize that we're framing long wavelengths as great and short wavelengths as bad. But like so many things in biology, it seems that it it may just be the balance that's important

and that long wavelengths can have this um kind of protective effect to some extent. Um but the way I'm thinking

extent. Um but the way I'm thinking about it is that LEDs may be problematic because of just how um how heavily they weigh one side of the mechanism. Is that

>> I I I think you've got it you've got it in one there >> as opposed to being quote unquote toxic, right? It would be like saying like uh

right? It would be like saying like uh we need all three macronutrients. I

suppose you could live without carbohydrates, but you know, you you know, fats, proteins, and carbohydrates.

And people will try and demonize any one of those depending on who they are. But

most most cultures, mo most humans evolved in the context of eating some amount of all three of those macronutrients, maybe to varying degrees, different seasons, etc. So, you can't just say that one is bad. You

know, fats are bad, proteins are bad, you know, carbohydrates are bad. It's

the waiting of them that that's going to um influence bi biology differently.

Seems like the same thing would be would hold for light. So under so let's frame this in people's minds under typical um lighting conditions with LEDs. So, if I

go buy a an LED light uh light bulb um and it doesn't say uh sunlight mimicking or full spectrum, how little longwavelength light is there

in that bulb compared to sunlight and how much shortwavelength light is there compared to sunlight? Not in terms of intensity because obviously the sun is generally far more intense than any

bulb. Um but in terms of the the

bulb. Um but in terms of the the distribution of wavelengths, what are we what sort of situation are we creating with those bulbs?

>> Okay. So first of all, you know, the way you've described it is absolutely the way I think about it and I think all our colleagues it's balance. It's balance.

You should be very careful about what you read on an LED box because people are saying sunlike

right now. I've never found, you know,

right now. I've never found, you know, commercially an LED that says that that's really gone anything significantly beyond 700. Right? So,

doesn't matter what they're telling you.

Um, I'm exceedingly doubtful >> that commercially anyone has got anything that does that because the only

way you could do that is to have a vast array of LEDs in a single device. So,

you know, have an LED at 670, an LED at 700, an LED all the way up to, you know, over a thousand. It's not realistic because it's expensive and it draws lots of energy. And the other thing is that

of energy. And the other thing is that we now have found that the mitochondria knows that it's a it's a compressed load of LEDs because if you put people under

a compressed series of LEDs like that, you don't get the same response or the same positive effect as you do if you put them under an incandescent light

where the spectrum is totally smooth.

There's no there's no ups and downs at the top of them. It's totally smooth.

Now, how a mitochondria does that is completely and utterly beyond me.

>> Well, it makes sense. The mitochondria

evolved under sunlight and sunlight is a smooth when you say smooth um as opposed to bumps, what Glenn is referring to is, you know, short wavelengths leading you said it's a continuum leading up to long

wavelengths. Sunlight has that. We'll

wavelengths. Sunlight has that. We'll

talk about incandescent in a moment. Um

and these LEDs have these spikes of short, medium, and longish uh wavelength light, but they're not actually mimicking sunlight.

>> No. And and isn't it amazing that mitochondria can sort that one out?

>> I think it's really cool.

>> And just makes me feel, you know, by the time by the time it's all over for me, um I'll have got one bite at this apple, but there's a load more to there's a load more there that that I think we're

going to find out they're doing things that are just inconceivable at the moment.

>> What about incandescent bulbs and fire?

I mean, I aside from being concerned that people are going to burn their apartments and homes down if they use candle light or fire light at night. Um,

how healthy is candle light? How healthy

is incandescent light with respect to the mitochondria?

>> So, um, I think we got to leave candle light out of it because to get enough light out of a candle, we're going to have to have, you know, copious amounts of >> and that's where people burn burn down.

>> Yeah. So, let let's let's and I noticed here in California, people have got lots of wooden houses. Let's stay away from that. a lot of what

that. a lot of what >> wooden houses.

>> Well, we had a serious fire issue area.

I mean, if you as you coming in the Pacific Coast Highway, you you may have noticed that used to be covered with homes. I mean, it was a devastating

homes. I mean, it was a devastating fire. Yeah.

fire. Yeah.

>> To a first approximation, the spectrum of light that you get from an incandescent light bulb is highly similar to solar light, right? So, it's

it's it covers almost the same range.

It's a smooth function. We drift gently from short wavelengths into medium wavelengths into long wavelengths. So in

evolution, we were wandering around in sunlight. Um

we then made the transition to fires producing the same light. And that's

quite interesting. Where do we use fires? We use fires as we move further

fires? We use fires as we move further north as as as we come out of Africa, you know, as we move into I mean, why did people It's beyond me having come

for this interview from Northern Europe in winter. It's beyond me as to why they

in winter. It's beyond me as to why they ever did that because it's grim. But

they had a light source that was very solar like and so there was no there was

no issue there, I don't think. Um, so

it's that it's that really very dramatic change that happens in the early 2000s.

Your body has never experienced such confined limited spectrum of light.

Um, never experienced it before. And you

know, one of one of the other issues that relates particularly to devices that people may use to increase the amount of uh longwavelength light they

get. Some of these devices are lasers.

get. Some of these devices are lasers.

You're no living entity has ever seen monochromatic light before. It is a totally alien thing to life.

>> Yeah. But please folks, do not shine lasers in your eyes. In fact, don't shine lasers on your skin. And the only people who should be shining lasers on on bodies are trained medical professionals for which there's an

important medical procedure being done.

I'm going to encourage you to be willing to answer this even though I realize it's a bit of an uncomfortable space for you. Um for artificial longwavelength

you. Um for artificial longwavelength light generating devices like the red, near infrared and infrared. Um some of

these are fairly high power. There are a growing number of papers certainly in dermatology um and pain relief. I mean not a ton of papers but actually it was a cover of

one of what I was told was one of the more prestigious dermatology journals is starting to evaluate what we call photobiomodulation with long wavelength light.

>> When you look at those devices, do you think that exposure to those can offset the negative effects of LED lighting um in a meaningful way? First of all, I

think the majority of them do no harm. I

suspect that the majority of them have a positive impact, but you know, we've opened up a lot of those devices, and they're pretty poor.

>> Poor in terms of the amount of energy, >> poor in terms of how they're put together, first of all, the value of the components. You when you get an LED, you

components. You when you get an LED, you know, an LED is like buying a car. You

can buy a bad car or you can buy a very good car. A lot of the LEDs are not what

good car. A lot of the LEDs are not what they say they are. Certainly when it comes to things like 670 nanometers, which is popular, they're hard to get.

So, they're not what they say they are.

And very often, they're not what they say they are a year down the road when they've been on and off for a long period of time.

>> Well, I think there's a range of qualities as well. Some are medical grade, some are not. Yeah.

>> Some are used by actively by medical clinics, some are not. Uh I I hear you.

I think it's like any industry associated with health and and wellness as it's called. I think there's there's a a range. Um so in terms of prescriptives as it relates to indoor

lighting, let's set aside longwavelength light emmitting devices. Incandescent

sound like the perfect solution. But can

I still buy incandescent bulbs?

>> Not in North America. You can't buy classic incandescents.

>> They're gone.

>> Yeah. I think I I signed a petition to try and keep them about 6 months ago and I don't know what the status of it is now. Um they you can still you should

now. Um they you can still you should still be able to get H hallogen bulbs which are almost identical to incandescent. They're a type of

incandescent. They're a type of incandescent and the point here is that um you can't have LED lights in ovens

because they melt. Okay. So generally

incandescent are retained for a few special reasons. The importance of these

special reasons. The importance of these um I think is is highlighted by something that should come out just before Christmas, one of our studies

where at University College London we have some buildings without windows um and they've got some pretty harsh LED

lighting in them. And what we did last year uh with those is we went in there and we measured the all the people staff

in there. We measured their ability to

in there. We measured their ability to detect color. Um then we gave them a

detect color. Um then we gave them a whole series of desk lamps, 40 watt incandescent desk lamps, and we said you don't have to look at this, just move

around, you know, if that's on your desk. But a lot of them were

desk. But a lot of them were architectural model makers, so they'd be sitting at their desk for a little bit.

at the time. Then they'd be going off gluing two bits of wood together.

>> Where's the light directed for these people?

>> Just directed down, not at their eyes.

>> No, no, no, no. It's supplementing their whole environment. So, we walked away

whole environment. So, we walked away from that and we left them I think we left them for two weeks. We came back and we measured their color perception

again and we got so much better an effect than we ever got with reduced spectrum longwavelength LEDs. It was

well I made us go back and do all the analysis again. I was really surprised.

analysis again. I was really surprised.

So with the with the LEDs, what you tend to do is the long wavelength ones. You

improve your perception of blue a bit more than your perception of red and there's a bit of a complex story and it's all over in 5 days. These

characters, their perception of blue and red both improved to the same extent and it was very significant.

And then we took the bulbs away and we thought, well, we'll come back six days later and we'll see where they are. We

came back, they were exactly the same.

They hadn't the perception had declined.

>> The improvement was maintained.

>> The improvement was maintained. We went

back a month later, the improvement was maintained. We went back a month later,

maintained. We went back a month later, the improvement was maintained.

>> So, I'm tracing all these people what their lives are like and the rest of it was it was in November, December, so they weren't getting much daylight. They

were in a rather Yeah. Well, they were in a situation like all people are in Northern Europe. Um, and then we had a

Northern Europe. Um, and then we had a problem. It was Christmas. Experiment

problem. It was Christmas. Experiment

ended. Um, but let's think about this.

These people not only had more significant improvement than they would get with red light, the effect lasted much longer. Now, one of the things that

much longer. Now, one of the things that makes me think now I go back. I go back and I think about our experimental results.

Why did I get such good experimental results in whatever it was I was doing?

Is it simply because we I am drawing my subjects from a population of human beings who are living under LED lights?

If I went and did those same experiments on a group of farm assistants, you know, or people who are doing surveying of the countryside, would I

get the same effect? I think that in the built environment, we are suffering from a suppression of our physiology. I have

to be careful here about not going over the top, but we're suffering from a suppression of our physiology via mitochondria that is just being produced by the built

environment. And a point that I really

environment. And a point that I really need to make here because I I now spend a lot of time talking to architects. I

spend more time talking to architects than I do talking to opthromologists or medics.

You put a building up, invariably the majority of the phases of that building will go over budget. It's rare for an a building to come in under budget. The

last thing to go into a building is the lighting. It is the very last. It goes

lighting. It is the very last. It goes

in after the glass. Okay? Where do you take your cut on your over expenditure?

You take your cut on the lighting. You

buy the cheapest LEDs you can and the cheapest LEDs have got the restrict restricted spectrum. So, and to add

restricted spectrum. So, and to add insult to injury on this to retain thermal regulation of the building, all

commercial buildings and you know all big buildings now, not domestic ones will invariably have infrared blocking glass. So you get the first hit on the

glass. So you get the first hit on the fact that your LEDs are pretty awful undermining your mitochondria. The second is you're

mitochondria. The second is you're isolated from the visual world outside by the infrared blocking glass. This

this is double hair and I think that double hair is is quite significant.

Now, we have had uh a major probably one of the world's largest architects firms that have just won a very big contract in the USA for a hospital walk through

the door and say, "What what is this about healthy lighting?"

And I know they're putting their money on the table on this one because they have a vast area where all their architects sit. It's like a aircraft

architects sit. It's like a aircraft hanger and they're stripping out all the LEDs.

So, what I'm gathering is that if people spend a lot of time outside, >> A, that's a good thing.

>> Yeah.

>> B, you probably don't need to supplement your indoor lighting environment. LEDs

might even be fine for those folks.

Although, you wouldn't recommend it.

Doesn't sound like they need to quote unquote supplement with incandescent or with long wavelength light exposure from a device. for people, which I think is

a device. for people, which I think is most people nowadays, who are under LED lighting a significant portion of the day in a building with glass that filters the bright sunlight to control

the temperature uh and make sure there isn't a lot of, you know, glaringly bright light coming in at certain phases of the day. They certainly should try and get outside.

>> Yeah.

>> When they can take their lunch outside, take a a call outside, get get outside.

light clothing is going to be fine because the the long wavelength light will pass through as your colleague discovered literally go through their body scatter etc. But they may need to

or choose to excuse me supplement with a hallogen or incandescent >> even just table lamp for a short period of time now and again especially it seems in winter this would be beneficial.

>> Yeah. And where I worry the most about uh light environments as it relates to diminishing mitochondrial function is in kids who are staring at screens, not

getting outside enough because of screens, etc. Classrooms, etc. What do we know about screen light? You know, I like many people will dim down my screen in the evening if I'm going to be on my

computer. I do wear short wavelength

computer. I do wear short wavelength blocking glasses after I wouldn't say after sundown, but after dark. really

helps my transition to sleep for obvious reasons.

>> I learned that um people's sensitivity to light in terms of how it impacts sleep varies quite a lot. Yes,

>> some people can stare at blue light and fall asleep, no problem. Other people do that, they're waking up in the middle of the night. I'm very sensitive to it, but

the night. I'm very sensitive to it, but the blood glucose elevating effects of of short wavelength light at night seem pretty ubiquitous. There's a study, I

pretty ubiquitous. There's a study, I don't know if you're familiar with it, um it was done, it was published in the Proceedings of the National Academy of Sciences. They had um people, I think it

Sciences. They had um people, I think it was kids actually, sleep under a 100 lux overhead light. So, their eyes are

overhead light. So, their eyes are closed. 100 lux is very dim.

closed. 100 lux is very dim.

>> And as compared to complete darkness, or it wasn't complete darkness, I think it was a uh like a 1 to 10 lux lighting condition, you saw elevated blood morning glucose.

>> Yeah.

>> Which is not good, right? That that

reflects a cortisol increase. So it's

not just about sleep, it's about blood glucose regulation, etc. So am I I'm summarizing here quite a lot of things and I'm speculating here and there as well. Do you think people need to

well. Do you think people need to supplement with long wavelength light if they're not getting outside enough or they work in one of these LEDrich environments?

>> Okay, let's let's backtrack a little bit particularly about the kids and screens.

So myself and a load of my colleagues have sat with a blue screen staring at it all day for days. um mindbogglingly boring

thing to do. It had almost no effect.

>> Oh, you've done that experiment.

>> We've done that experiment.

>> I thought you just describing your life.

>> Um and um >> I think the answer is that the blue in most of those screens is actually rather long wavelength blue. So, it's blue

pushing pushing 450 plus. So, it's not in that danger zone which is which I regard as 420 to 440. I think it's outside it and I know we talked at one

point to a major American uh computer manufacturer about this issue about the screen. So I am not as worried about

screen. So I am not as worried about that as I thought I would have been. But

there is a separate issue and it's one that the pediatric opthromologists are very concerned about and that is

particularly close work in kids. close

work combined with a lot of screen work and the issue of myopia.

>> Close work being staring at something within a foot or or two.

>> Yeah. So, and myopia. Now, this is a very big issue in um in Asia >> uh and in China and we know that the

absence of longwavelength light is a driver. My problem is I can't work out

driver. My problem is I can't work out why. Now I should fundamentally be a

why. Now I should fundamentally be a pragmatist and say if we know it's a driver then let's just supplement it.

>> When you say it's a driver it's it's creating this problem.

>> It is part of the thing that's creating this problem. Now myopia is a really big

this problem. Now myopia is a really big issue because okay we can control myopia by just giving you different lenses.

Right? So your child will be able to read the text even though they've got myopia. The trouble is that when that

myopia. The trouble is that when that child reaches 40 or 50, the retina has been stretched because the eyes grown too long. And as the retina stretches,

too long. And as the retina stretches, as you age and you lose cells, so the retina becomes a little less cohesive, you get tears and you can get a form of macular degeneration.

>> Yikes.

>> So this is very a major concern particularly in China and they've taken a number of steps to deal with it. One

of which, for instance, is in the classroom, they put a bar in on the desk, so the kids can't actually sit too far forward to read the text. Whoa.

>> Right. So to increase the distance, they've also got into the red light, but part of the problem there is they've used lasers.

So they've got a restriction in myopic development but at the same time when you go back and look at them um there

are spots in the retina where the laser has affected >> negatively >> negatively is burning out pieces of retina.

>> Yeah. And and and but you know people come along and they say look we only used 10 mills per centime squared. Same

as an LED. The thing that they don't get is that laser light scatters in a very different way from LEDs. LED light

scatters unifor uniformly.

>> Why do you think they use lasers?

>> Because it sounds good. We're using like we're doing something more powerful.

That's a problem around this whole industry. We're doing powerful things.

industry. We're doing powerful things.

>> Now laser light does not scatter evenly when it hits tissue. It forms something called costics. And costics are the

called costics. And costics are the sorts of things you see sometimes on a shallow lake where it's rippling and you get bright spots and you get dark spots.

Those bright spots are what you get in laser light these costics. So the energy is tripling or quadrupling in certain areas. So I mean I didn't know what a

areas. So I mean I didn't know what a costic was and I started to talk to physicists never reiterate on you never ever use a laser unless there is a

profound medical reason for doing so.

and certainly myopia which is going to be it's a ticking time bomb. No, no

current politician is particularly concerned because it's going to be another person's problem in the future.

So windows in in classes very important >> and not tinted windows.

>> Not tinted windows.

We're currently talking about putting a few incandescent lights in. Schools

generally are stretched for money >> and their first reaction is um this is going to cost us a lot more. Well, the

answer actually is put a dimmer switch on the on the incandescent light bulb.

Even though it appears dim to you, it's still producing loads of infrared light because it's getting warm. The other

thing that we've not touched on, which is, I think, very important in the architectural world and the school world, is that all plant matter reflects

infrared light. You grab a plant out

infrared light. You grab a plant out here in California where maybe it's 80 degrees, the leaf is not hot. Why does

that happen? It's because it reflects infrared light. Now, if you go up to a

infrared light. Now, if you go up to a plant in brilliant sunlight and you put your measuring equipment on it, the light that's being reflective is just a

small reach away from what we think the the smallest therapeutic dose could be.

So planting trees to reflect the infrared light that is available to you is very important. Architects are really getting that one.

>> Does it have to be trees or can just be indoor plants and having an incandescent source?

>> Well, okay. Have an incandescent source, but have also plants on the outside >> that are that are getting sunlight because they're going to bounce the

infrared back to you. One of the physicists in our lab, um, Edward Barrett, has a fantastic infrared camera and he goes around taking infrared

photographs. And we were in a we were in

photographs. And we were in a we were in a an office building and there was some blackout blinds, very thick blinds. And

when we looked for the infrared camera, there was a small fire at the bottom of these curtains. I mean, just really

these curtains. I mean, just really surprised. And then we pulled back the

surprised. And then we pulled back the curtain and there was a row of plants.

>> So um and there is the name completely escapes me. There is a city in the

escapes me. There is a city in the Midwest where the authorities planted something like a thousand trees. And

what they did was they measured blood markers that were blood markers of stress including compliment related protein which is a sign of systemic inflammation. and they planted these

inflammation. and they planted these trees and they went back I think two or three years later and measured these metrics and they got a significant

reduction. Now that is interesting,

reduction. Now that is interesting, right? So my big question and it's one

right? So my big question and it's one that I'm trying to get ethics to do now is what happens to your blood as you pass from a concrete building. I sit you

in a concrete building for 5 hours.

Yeah, it's horrible. You're getting no infrared light. You've got infrared

infrared light. You've got infrared blocking windows. You got LEDs. What

blocking windows. You got LEDs. What

happens when I wheel you into a park?

What happens when I wheel you into woodland? You know, you feel so much

woodland? You know, you feel so much better. You know, everybody says, "I

better. You know, everybody says, "I feel so much." Well, if some if you feel better, something's happening. What is

happening? So, it's not only about the light that we have in the built environment. It's about the glass that

environment. It's about the glass that we have in the built environment. And

it's about plant matter. Plant matter.

Should we be planting plants for instance on the north side of buildings which are tall because they will hit the light level and they have the capacity to reflect it back through into the building.

>> I can tell you've been spending a lot of time with architects and a couple things are are really striking. one,

it's very clear that as we become more and more modern as a species, we're going to look for more uh you know cost and energy efficient ways to do things.

LEDs are a good example of that and I think LEDs have been very beneficial and you know across a number of different industries >> but that >> you know as we move away from

agricultural living for most people um nowadays people even will just have food delivered as opposed to going to restaurants that's happening more and more and I think it's a required effort to bring the critical elements of the outside indoors.

>> Yes.

>> And it sounds kind of crazy but people will you know exercise indoors. I try

and exercise outside if I can, but I can't always do that. But we're now talking about bringing longwavelength light indoors and bringing balanced full spectrum light indoors. And if it's as

simple as bringing some plants, you know, putting plants around a building, keeping the tinting off of windows, maybe it I could see where that might cause some issues with uh, you know, regulating temperature and the

downstream costs of that, etc. But, you know, having some long wavelength emitting sources, maybe it's uh maybe it's an

actual longwavelength aka red light, you know, somewhere near a plant or a series of plants in and because not everyone can change their their internal environment, their apartments, etc. I I

must say in the last >> probably 18 months, I've made some pretty serious effort to get in front of a long wavelength emitting device. I

just my own personal experience is that by doing that and I do do it early in the day. I do not use protective eye

the day. I do not use protective eye covering because I'm comfortable with with those wavelengths. I sometimes will close my eyes for portions of it. But I

must say, and I don't think this is placebo, but who knows, I find that it produces a tangible increase in in just energy and feelings of well-being for a

substantial amount of time afterwards for me. And but that's on a backdrop of

for me. And but that's on a backdrop of already doing a number of other things including trying to get outside for brief 20 minute or even 10-minute walks, grab a little gulp of sunshine, as I call it. Not really gulp. I I I think

call it. Not really gulp. I I I think that the more we can get outdoors, great, >> provided we don't sunburn, >> but we need to start bringing certain

elements of the outdoors in to classrooms, hospitals. I mean,

there's this phenomenon of ICU psychosis where people don't have access to uh sunlight and circadian rhythm information. They're being woken up in

information. They're being woken up in the middle of the night and they literally de they're not psychotic and they develop a transient psychosis that resolves when they leave the hospital. I

mean, I feel as you can probably tell very very strongly that lighting is so critical for immediate and long-term health. And I agree with you. I think we

health. And I agree with you. I think we um not to sound catastrophic but that if we don't um no pun intended short circuit this uh uh excessive short wavelength light issue that we are going

to see more and more metabolic dysfunction more and more visual dysfunction myopia and for people with neurodeeneration or or a bias a genetic

bias toward it or or a you know maybe they uh occupational hazard related bias toward it that if they don't get the protective effects of long wavelength light I think It's it's going to be really serious.

>> Yeah, I I completely agree with you. I

mean, we weren't sticking our head above the parapit three or four years ago, but we are now. We think this is a significant public health problem. And

some people, we've been approached by a few critical care units saying, should we, you know, what do you know what about changing our lighting? I mean, the architects have taught me one or two

things. So they they say cost to me

things. So they they say cost to me because you they're commercial. So they

say things like um okay well if that gets your patient out of intensive care unit one day earlier what does it save you?

>> With one group of architects we've talked about relight changing the lighting in a building to having major reurbs on it and oh you know the the the

owners are you know they're going do we need this you know etc etc. And the architect turned around and said, "How many days did you lose sickness in this building last year?" And of course,

they didn't know the answer, but it put them really on the spot. But the

architect said, "You should look at the larger economic model here, and that includes the health, perceived health of the individual, but it may have

beneficial effects for you in terms of reducing costs." M I I I think they put

reducing costs." M I I I think they put their finger on that really quite quite sharply >> for people that are on a real budget.

>> Um and like most of us have to rely on LED lighting.

>> Um hopefully they're dimming their lighting a bit in the evening, not relying so much on overhead lighting, trying to get their circadian rhythm correct. And in the daytime getting

correct. And in the daytime getting outside is get their sunlight in the morning, etc. And they want to get some more balanced or long wavelength light.

and they want to do it in the least expensive way possible.

Even though candle light is not very bright, getting a I would recommend a odorless uh cuz we're learning all this stuff about the odors from candles. A,

you know, an odorless like pure beeswax candle that provided it safe. They can,

you know, at their desk in the evening or next to maybe even on their nightstand, they have a candle while while they read. Just getting a bit more long wavelength light. you know, you know, as you say, supplementing with long wavelength like here and there,

maybe while even they're on their phone or their tablet before sleep.

>> I feel like these things ought to make a meaningful difference over time. They're

very low cost, >> provided you don't burn your structure down. They're safe and even better, it

down. They're safe and even better, it sounds like, would be to get a hold of an incandescent or or H hallogen bulb.

But, um, I feel like this is something that most anyone could do and seems very very healthy to do. Well, I am 100% behind the idea that firstly that this

will can change public health and secondly that it should be done at almost zero cost because that is a potential. Okay. So if you look at say a

potential. Okay. So if you look at say a number of my colleagues and this includes myself um in the kitchen I have got a H hallogen lamp. So when I get up

in the morning and you know you you're spending that 45 minutes that really should be 10 minutes but you know you're fuffing around doing stuff there's a H hallogen lamp there on at the right

time. It's not desperately bright but

time. It's not desperately bright but it's there at a critical time during the day.

>> What color does it appear?

>> Ordinary white light.

>> Okay. But it's full spectrum.

>> But it's full. A proper H hallogen lamp is just a certain kind of incandescent that has potential longer life in terms of its shelf life because there are reasons you should keep it, reasons you

should have it >> and just do that.

>> Great. just, you know, um a H hallogen lamp and particularly if you if you can afford to dim it, um it'll last almost

forever because if you just turn the power down, which increases the amount of infrared light, the bulb will last for ages. Absolutely ages.

for ages. Absolutely ages.

>> And you're using this in the morning.

You could also use it in the evening.

And if you dim it down, it's not going to alter your melatonin level, circulating >> rhythm. and and if you dim it down, your

>> rhythm. and and if you dim it down, your energy bills should not go up.

>> Um, so I believe profoundly that we can affect public health and we should affect public health at a highly

economic way. Um and that's kind of so

economic way. Um and that's kind of so we are working hard on what's the minimum what's the minimum what's the minimum you know in in critical care

units a big one that we really are trying to dent is nursing homes where these people spend all their time in beds or they're you know they're away from windows. Can we wheel them all in

from windows. Can we wheel them all in for breakfast and actually have a heat source, an incandescent heat source >> to provide incandescent light, but at

the same time use that heat. So the

architects used to say, "Well, if you want me to change all these lighting, you know, what am I going to do with all this excess heat coming off ceiling lamps?" Well, they they've turned around

lamps?" Well, they they've turned around now. They're saying, "We'll put them

now. They're saying, "We'll put them lower down and maybe we'll use the heat to circulate in the room." There's lots of imaginative ways uh around this. You

know, there's there's 50 PhDs in in this with with some really simple winner experiments.

>> It's great. I mean, I I'd like everyone to think about their lighting, indoor lighting environment, how much sunlight exposure and um shortwave length shifted LED exposure they're getting during the

day. Not because I'm, you know, really

day. Not because I'm, you know, really into like extreme biohacking. I'm

actually not. I just think that whatever we're missing from the out ofdoors that we need and is healthy for our mitochondria which clearly involves long wavelength light, your work has demonstrated that beautifully and the

work of others of course you're always so good at attribution. So I I want to acknowledge you for that um by doing it as well. I think people should do it and

as well. I think people should do it and if it's an incandescent bulb or a h hallogen or um candle light um it seems like it would make a meaningful difference. Speaking of meaningful

difference. Speaking of meaningful differences, uh before we uh part ways here, I would love to hear a story that you were starting to tell me before we

recorded about a child with a mitochondrial disease and how some of this stuff about light and mitochondria was actually useful in that context.

>> Yeah. So we we're doing clinical trials and I'm quite optimistic about some of them. But um there is a specific group

them. But um there is a specific group of diseases called mitochondrial diseases where the genetic code mitochondria have got their own DNA. The

genetic code for making ATP gets disrupted.

Um and that can be mild or it can be very severe. Um some of these children

very severe. Um some of these children do not make it beyond 25. Um typical

reasons are heart failure etc. Some of them are very um bedbound and crippled by the disease.

Others managed to walk around and function to a first approximation. And I

I started to get emails from people who said you know you were showing red light. You're using word red light and

light. You're using word red light and mitochondria improving mitochondria. My

child's got mitochondrial disease. And

um I said I don't have ethics for that.

you know, I can't pass any real comment.

If you chose to do something, then I suggest you might consider doing this.

And the first child that did do that had a I would say gut-wrenching improvement.

We were devastated by its effect.

>> Positive effect.

>> Positive.

>> Over here, we when we say gut-wrenching, we mean it was negative. Oh, no.

>> You're saying I It was eye watering for you guys is negative. gut-wrenching is

positive over here. Eye watering is positive and I'm just teasing.

>> Okay. So, so the we were looking at simple metrics which is how much they could open their eyelids. It's called

tosis, right? Couldn't open their eyes.

Um this child, the first child within a month or so was had semi-mobility.

>> I got a video of her working walking to school.

>> Um I went to the bathroom and sobbed.

done something that's really helped someone. Then we had another couple of

someone. Then we had another couple of kids and they all had small improvements. We got a clinical trial

improvements. We got a clinical trial for it. And our biggest problem is we

for it. And our biggest problem is we couldn't get enough kids into the study.

The density of kids with mitochondrial disease in the UK, we got funding for it was just too low. So one of the things I've got to do sadly when I go back um certainly before Christmas, I've got to

wrap that up and hand the money back.

I'm just going to say just could not get the kids and some of them, you know, as I told you, you know, when that disease digs in badly, we can't do anything about it. Some of those kids were just

about it. Some of those kids were just so sick. Um, you know, it was a major

so sick. Um, you know, it was a major effort to get them to the hospital to assess them. Um, but let's take a a

assess them. Um, but let's take a a defocused image on this. In

theoretically, red light should help kids with mitochondrial disease. it will

do absolutely no harm whatsoever. And I

generally say if all of this is a pile of rubbish, A, I'll look an idiot, but I don't think I am going to look an idiot.

B, you will not have wasted money on something that's just completely worthless. So, I'm talking to people now

worthless. So, I'm talking to people now and I'm saying, "Okay, why don't you think about changing the light bulbs in the home to get just get that extra bit of red light to help help you through?

We've got a we've got a a trial for a retinal disease coming out shortly.

Don't I don't know the results. They

won't show me. Probably because they know I'll talk. Um and it's for a disease called retinitis pigmentotosa.

>> Very common.

>> And we've had a fantastic response from a donor in the states who has given us some money and the next project in that line is changing the light bulbs for

patients with retinitis pigmentotosa.

I'm partly working at Morfield's Eye Hospital. Supposedly it's got the

Hospital. Supposedly it's got the biggest opthalmic outpatient population in the world and we do have enough people with retinitis pigmentotosa. Um

so I'm going to kick that off towards the end of this year. Everything's

pointing towards light bulbs.

Everything's pointing towards and I would at this point say and I' I'm not saying it for the first time here. I've

shouted about it for the last six months. Morefield's Eye Hospital is

months. Morefield's Eye Hospital is building a brand new hospital. Looks

great. It's all in glass. that blocks

infrared and it's got the world's worst it's going to have the world's worst LEDs put in it.

You know, we we need we need to learn, but it's apparent to me we're going to have to learn slowly as with so many things with human health. But listen,

Glenn, um I want to thank you on many levels. Um first of all, for taking the

levels. Um first of all, for taking the long trek over here from the UK. Uh we

we brought have some sunlight to offer you. Um

you. Um >> Oh, look. I'm on the human podcast.

That's a big plus in life.

>> All right. I'm also I got out of London which was gray, grim, cold, and wet.

>> You didn't have to talk too hard to get me over here.

>> All right. Well, we're happy to have you here uh in the studio sharing all this knowledge. And also, I I really want to

knowledge. And also, I I really want to thank you for shifting your focus of research. Uh we won't waste people's

research. Uh we won't waste people's time by talking about the various things that you and I worked on for years. We

were in slightly overlapping fields and then different fields and we would overlap again. But we go way back and

overlap again. But we go way back and you've always done such meticulous and um and really beautiful work. uh but I think you and I um have shared with one another and I'll share now that you know

at some point one reaches like a juncture in their career where you kind of go you know how can I make the most positive impact and um a few years back when I started seeing the studies that

you were doing on on bees and mice and um and then humans evaluating how different wavelengths of light can impact visual function mitochondrial health and the number of really terrific

collaborators that you've brought in around that and again I I I love the way that you give such a ready attribution to the other people in the field and and also that you are willing to be vocal

about what people can do. Um scientists

are often afraid of that. You give

people meaningful suggestions about how they can um perhaps improve their health, their vision, etc. using lowcost or even in some cases cost-saving technology. So, I could go on and on

technology. So, I could go on and on here, but I really want to thank you for sharing all this knowledge, for doing the work you do, and for being a voice for public health as it relates to indoor and outdoor lighting. And uh I

really look forward to seeing what you do next, and it's uh a real pleasure for me to sit down with a long-term colleague. So, thank you.

colleague. So, thank you.

>> I thoroughly enjoyed it. Thank you.

>> Thank you for joining me for today's discussion with Dr. Glenn Jeffrey. To

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