Light is essential to life as we know it. Plants rely upon sunlight to generate chemical energy, which is stored in their tissues and fuels various life processes. In turn, animals like us convert the energy from the food that we eat into mechanical energy.
Furthermore, we depend upon light energy entering our eyes in order to see and interact with the world around us, and to align our biological clock. Everything that you do, and everything that you see around you, is the product of light.
Given its fundamental role in our biology, it shouldn’t be too surprising that patterns of light exposure are intimately linked to our health and performance – in ways that research is only just starting to elucidate.
For instance, we’ve learned that insufficient environmental light may lead to structural changes in the brain, and to poorer cognitive performance. Importantly, different wavelengths of light may have specific effects. For example, short-wavelength light (or blue light) has been shown to modulate blood pressure. And some studies have suggested that ultraviolet light might protect against weight gain and cardiovascular disease, as well as prevent metabolic derangement and type 2 diabetes. If you want to take a deeper dive into this topic, I’d recommend you check out Dan’s TED talk on the subject (embedded below).
But another form of light exposure, which you’ve probably heard about before, and which we haven’t had the opportunity to address here, until now, is red light therapy.
Like hundreds of technological advances that we take for granted today, the medical application of red light therapy appears to have originated from NASA. Scientists developed red light-emitting diodes (LEDs) to help promote growth in plants on space shuttle missions. From there, red light was investigated for potential medical uses, perhaps to combat the adverse effects associated with space travel in astronauts.
These LEDs were shown to stimulate energy processes in mitochondria – the organelles where our cell’s energy is generated. By augmenting mitochondrial function, and enhancing energy production, you would expect cells to be better able to repair and rejuvenate themselves. But is that indeed the case?
Since red LEDs were invented, thousands of studies have been performed to figure out if red light therapy can improve health and human performance. If you do a search on red light therapy in Google, you will be inundated with health claims spanning an extraordinary range of conditions, from cellulite to osteoarthritis to carpal tunnel syndrome to Alzheimer’s disease. If you’re like me, that might raise some red flags in your mind.
So, are the benefits attributed to red light therapy authentic? Or is this just snake oil for the Instagram era?
Our guest for this episode is uniquely qualified to shed light on this.
In this episode of humanOS Radio, Dan speaks with Michael Hamblin. Dr. Hamblin was (recently retired) Principal Investigator at the Wellman Center for Photomedicine at Massachusetts General Hospital, and an Associate Professor at Harvard Medical School.
There is perhaps no one alive with greater expertise in the health effects of red light therapy and near infrared light than Dr. Hamblin. He is a prolific researcher in photomedicine, having published over 400 peer-reviewed articles on the subject, as well as authored and edited 23 different textbooks.
In this interview, Dr. Hamblin explains:
- What photobiomodulation is, and the molecular mechanisms through which it works its magic
- What wavelengths and intensities of light are used for physiological effects
- How photobiomodulation has been investigated for athletic performance, skin health and rejuvenation, and psychological conditions
- When and how to use red light therapy for exercise performance and recovery
- How red light functions as a healthy stressor to elicit anti-aging effects
- And more!
Ted x Talk
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Michael Hamblin - 00:00: Red light is still probably the single most popular type of light used in photobiomodulation, but it's being rapidly overtaken by near infrared light.
Dan Pardi - 00:12: If you've been listening to the show for a while and following our work on humanOS, you may be aware that light is a subject that I am fascinated by. In September of 2018 I gave a talk at TEDxMarin entitled, How To Optimize Light For Health. In September of 2019 I gave a talk at the Ancestral Health Symposium at UC San Diego on the effects of sunlight, including ultraviolet or UV radiation on various aspects of health including cancer, autoimmunity, and metabolic health.
00:45: I've also done many episodes now on humanOS Radio on light and health, and I'll include links to those shows in the show notes for this episode here. As you might've guessed at this point today's show will also be on light, but the focus is on something I have yet to cover. Red and infrared light. The claims of what red and near infrared light therapy can induce can sound perhaps unrealistic.
01:10: Is red light actually good for many different health issues, or is it just some form of snake oil? But what if it is healthy for our physiology in many ways? Perhaps then we can also think of red light as a missing nutrient of sorts. This is why I'm very pleased to have with me today, Michael Hamblin.
01:31: Michael is an associate professor at Harvard Medical School. He has over 400 peer reviewed articles on the subject. He's authored and edited 23 different textbooks, and in 2017 he received the first ever Lifetime Achievement Award in Photomedicine from NAALT, the North American Association for Photobiomodulation Therapy. Michael, it's a pleasure to have you with me today. Welcome to humanOs Radio.
Michael Hamblin - 01:56: Thank you for inviting me to be on your podcast.
Dan Pardi - 01:59: Let's start with some basics. What is photobiomodulation, and does it go by any other name?
Michael Hamblin - 02:07: About five years ago, the experts in the field came to a consensus decision to call it photobiomodulation. And as you point out, the reason for this, as we would say, a whole cacophony of other names, and there were things like low-level laser therapy, low-intensity radiation, cold lasers, soft laser. Low, this, that and the other, and one of the reasons for that is that the field developed from laser therapy. So when Endre Mester discovered it, he used the laser and that was in 1967 and since then people use lasers all the time.
02:50: The reason they called it low-level is that you can use lasers for cutting and burning tissue, so-called surgical lasers. So that was one the reasons of trying to distinguish it from high-power surgical lasers, but low as a very a subjective term. I mean you can't define low. What do you mean by low? And also in recent years, maybe the last 10 years, LEDs have become way more common than lasers.
03:17: And there are many reasons for that. One is that lasers are expensive. You need to have laser safety training courses. You need to wear laser safety goggles. People would go to laser therapists to have a laser Chanel and pay whatever, $50 for a session of having a laser Chanel. When LEDs came in, people realize that these were safe. They're cleared by the FDA for as being safe for general health and wellness applications.
03:51: It's different from FDA approval, which requires controlled clinical trial for a medical indication. That pleadings are approved as safe of general health and wellness applications. Perfectly fine to sell LED devices. There are literally hundreds of them on the internet. [inaudible 00:04:10] you can search them LED therapy or LED arrays, You get all sorts of wavelengths and powers.
Dan Pardi - 04:19: This therapy went by many different names. It originated because in the '60s they started to use high powered lasers, which are used for cutting in surgery. The first application of red light was lower energy lasers since that's where it originally came from. That's what the name was. With the invention of LEDs, you could now have more accessible, cheaper delivery and it didn't have to be in a lasers. Overall, the name of the category changed a photobiomodulation. What we're really talking about here is red light. What are the wavelenghts that we are talking about?
Michael Hamblin - 04:51: Red light is still probably the single most popular type of light used in photobiomodulation, but it's being rapidly overtaken by near infrared light. The near infrared light, depending on how you define it, is invisible. Some wavelengths around 800 nanometers are dim red, so you can see them. But once you get to beyond 850 they're invisible to the human eye. But that doesn't mean they're not highly effective.
05:21: If I had to choose, I'd say that near infrared, say 850, 870, 904, 940 is more effective than red lights. Lots of LED devices because you get LEDs and the red or the near infrared and you usually use them in a rays where they may be tens or even hundreds of individual diodes mix and match. So quite often you'll get 660 nanometer LEDs interspersed with 850 nanometer LEDs. That's a very popular combination.
Dan Pardi - 05:57: These different frequencies might be having different facts, but they're all within the range of red to infrared?
Michael Hamblin - 06:03: Yeah, and there is some evidence that by mixing red and near infrared, it's greater than the sum of its parts.
Dan Pardi - 06:10: How intense does the light need to be in order to have a physiological effect? Does intensity matter?
Michael Hamblin - 06:18: Yep. Absolutely. Intensity is usually measured in power density and that's milliwatts per square centimeter. But a very important metric is the total power. So the total number of watts and energy that are hitting the body. Of course, power is definition energy per unit time, but another important concept is the total amount of energy you to live up. So even if you had a relatively low power device, if it was shining light on the body for a long time, the joules of energy would add up.
06:52: What a lot of people don't realize is that the sun is actually quite powerful in the optical wavelengths, and depending on where abouts you are in the country and what time of day it is, but if you were to sun bath for one hour, at mid-day you would absolve a million joules of energy in one hour sun bathing in your body, and that's because you're exposing a lot of surface area.
07:18: If you have a large array of LEDs, and you've probably seen LEDs beds like tanning beds except the UV tubes have been replaced with red near infrared LEDs. If you climb into one of these whole body light beds and again absorb hundreds of thousands of joules of energy half an hour, that's sort of time. Now this is quite a different concept from laser therapy, right? Because laser therapy was delivered as a small focus spot usually to what they call, points.
07:53: When you have some kind of the pathology, let's say you had arthritis in your knee, they would shine points all around your knee, like every pros points. And the laser therapists thought there was some art in choosing the exact points to shine the laser. When you using LEDs, you basically wrap your whole knee around with a flexible LED array. So you don't worry about points, you're more interested in learning the total number of joules, which is way higher than you would deliver with a laser.
Dan Pardi - 08:26: You've indicated that some people would be using this for arthritis in the knee. Let's talk about what photobiomodulation has been investigated for, and in this discussion, and maybe we could talk about the areas that have the most amount of work behind them and the areas that you find to be most interesting now given the most current studies on red light and different physiological processes.
Michael Hamblin - 08:51: Right. Let's divide this into two areas. If you're going to use photobiomodulation for general health and wellness, and we're really talking about skin and the muscles because these are usually like whole body light beds or big arrays, right? And the muscles have a lot of mitochondria, and the mitochondria are the parts of the cell that absolves the light. And that helps athletic performance recovery from exercise. And a lot of army of things.
09:20: If you're going to treat some disease or pathological condition or an injury, then you generally focus the light. It could be a laser or it could be with a small LED array on the part of the body that needs it. And this is quite often it's joints, tendons, because they're painful, they're inflamed. There's not really good medical treatments for tendinitis, arthritis, all these things. Tennis elbow, carpal tunnel, yeah, shoulders, feet. So diabetics have a lot of problems with their feet.
09:57: So there's all these parts of the [inaudible 00:09:59]. Quite often they're in the limbs, the joints, but there are also applications deeper within the body. And people have realized if you have a big LED array, you can put quite a lot of energy into the body. Some people are a bit obsessed about optical penetration into tissue, and they think the light has to get deep inside the body, which totally doesn't if you look at the tissue optics.
10:25: That doesn't mean delivering light to the body is not helpful with like lung conditions, kidney failure, a lot of immune problems. My personal area of interest is in the brain, so when you put near infrared light on the head it helps a whole variety of brain disorders. Like now,` she's had a stroke or a head injury or even getting a bit old so your memory's going, maybe you've even got Frank dementia.
10:54: It also helps a lot of psychiatric disorders, so depression, anxiety, insomnia, drug addiction, ADHD, autism, all sorts of psychiatric or psychological conditions. Now, there are some applications that make money and these are generally in the cosmetic [inaudible 00:11:16] applications. Hairy growth is a big deal. There is caps and cones and things you can put on your head to get your hairy growing if the old androgenetic alopecia is just starting. If you let it go too far and you've got a shiny bald head it's not going to work. Right. But it does work when you just notice some thinning hair.
11:37: Now skin tone and skin rejuvenation is a big deal, so there's lots of LED face masks on the market that will help with fine line and wrinkles, luxe skin, pigmented spots, all sorts of aesthetic things. And then the other area is fat loss because this it is, is such a huge problem. Now it turns out that photobiomodulation is quite good for fat loss if you combine it with exercise. If you lie there in your LED bed and you think that's going to melt off you, it probably won't.
Dan Pardi - 12:10: Too bad.
Michael Hamblin - 12:10: Because the photobiomodulation stimulates the muscles, the bones, the fat much more effectively than if you just the exercise on its own.
Dan Pardi - 12:20: Interesting. So would you want to use red light therapy before or after exercise then?
Michael Hamblin - 12:26: Good question. I mean some people even do it during... So there's one device I saw was an exercise bike, was all the near infrared. There were actually lamps, not LEDs, but just same thing arranged around this exercise bike. The idea you would get on the bike would start cycling and the near infrared light would come on at the same time, but I don't think you need to do that. You could do it before, you could do it after. Typically, it's used as part of a training regimen. So if you go out training, you come back, you have 15 minutes photobiomodulation, and you do that religiously every time you go training, your performance will be a lot better than if you admitted the photobiomodulation.
Dan Pardi - 13:09: Interesting. Is there a time window in which you should get exposure to the red light after exercise or does it have to happen within the day?
Michael Hamblin - 13:17: Yeah, probably. You're just going to do exercise or race or something, you would have the red light maybe a couple of hours before, but some people do it directly before, which helps.
Dan Pardi - 13:29: I see.
Michael Hamblin - 13:29: But if you do the thought of a training regimen, it's quite often to use the light afterwards. Because you come in from training or a bit sore, and it definitely helps muscle recovery a lot.
Dan Pardi - 13:41: Well that is the new exciting field and exercise is all about recovery. 10 years ago it was more about advanced training techniques and now people are realizing that so much of the benefit occurs after the stimulus. So all the therapies, whether it's ingestion, muscle massage, or now, red light therapy, anything that can improve your recovery capacity is of interest to athletes. I know that. How far does red light and infrared light penetrate into the body?
Michael Hamblin - 14:07: That's a good question. It's endlessly debated, and you know there's literature on tissue optics. The best wavelengths is in the low 800 so penetration that's being shown multiple times.
Dan Pardi - 14:19: Okay.
Michael Hamblin - 14:20: And it depends what you mean by penetrate. If your tissue optics, you calculate the distance to one ovary, and one ovary is 37% so it's the distance into the body where the light is 37% of its initial intensity. Right. And that's in the near and treads about a centimeter I think generally nobody really knows how many photons you need to get inside you. Say in your brain, right? In your brain generally doesn't see much light, even though relatively number of near infrared photons could be highly active in the brain.
14:56: And having said that, whenever you shine the light on the body, it's absorbed by blood that's circulating. So a lot of blood circulating in the skin. So a lot of the light is absorbed by the blood and we really don't know how much of the benefit is from the light penetrating deep inside the body, and how much being absorbed by the blood, and beneficial things being circulated around.
Dan Pardi - 15:23: Does the application need to be local?
Michael Hamblin - 15:26: In many parts of the body, the lower legs, right? The bones are fairly near the surface and it's being shown if you shine light on the lower legs, you actually stimulate the bone marrow to release stem cells. That also applies to the head. I mean there is bone marrow in the skull. Putting the light on the head might stimulate the bone marrow to release stem cells. There's three issues, direct penetration of photons into the tissue of interest, systemic absorption by circulating blood and stimulating bone marrow if the bones are relatively near this.
Dan Pardi - 16:02: The red light will also penetrate into bone or through it.
Michael Hamblin - 16:06: No. Bone it's scattering, but it's absorbing. It's white, right? Things that are white scatter light, things that are colored, absorb light.
Dan Pardi - 16:15: Let's talk about mechanisms then. We talked about the origin of where it came from and the naming. We've talked about some of the therapeutic areas that have been explored. Why does red and near infrared light therapy have an effect on our physiology? What is it doing that's causing some physiological change in the body?
Michael Hamblin - 16:33: The main mechanistic receptor is the mitochondria. As you know the mitochondria, the powerhouse of the cells, eight glucose and oxygen, and produce ATP and water and carbon dioxide, and they have a lot of chromophores. And they have chromophores that absorb in the near infrared. Such chromophores oxidase, which is unit four of the mitochondrial respiratory chain is a favorite chromophore, but it's almost certain that other mitochondrial chromophores are involved.
17:04: So you got more ATP, more oxygen consumption, but you got a lot of signaling arising from the stimulated mitochondria. Signaling, is small main mediators of the signaling. You get a brief thirst of reactive oxygen species, which can be compared to the ROS you get from exercise, which is not a huge amount. It's not chronically prolonged. It's a brief thirst to stimulate things. You get, as I said, you're more ATP. And from that you can get cyclic AMP. There are a lot of cyclic AMP responsive transcription factors.
17:40: You get nitric oxide released, it's uncertain whether the nitric oxide comes from prolasis thought nitric oxide, but definitely get more nitric oxide. And you also get substantial changes in calcium within the cells, within the mitochondria. So these are the four secondary mediators, and then these secondary mediators trigger active transcription factors.
18:06: We did a review recently where no less than 14 separate transcription factors had been reported to be activated by light depending on the tissue and the condition and so forth and so on. There are models when a single exposure to light, a mouse model has lasting effects for four weeks. We showed that with the traumatic brain injury models. So we did a TBI to the mice. Shone light on their head for hours after we hit their heads and their neurological function continued to steadily improve for four weeks.
Dan Pardi - 18:42: So if somebody gets a head injury on let's say a football field, then if it is a daytime game, they should not have their head covered, but I should try to get some light if it's in a sunny day.
Michael Hamblin - 18:52: I think the best thing would be to put a near infrared helmet on their head.
Dan Pardi - 18:56: Is the intensity of a near infrared helmet more intense than what sunshine would deliver?
Michael Hamblin - 19:01: It's a better wavelength.
Dan Pardi - 19:03: Okay, I see.
Michael Hamblin - 19:04: I mean the peak of sunlight is in the green around about 520 nanometers, and that doesn't go through hair very well, it doesn't go through the scalp and the skull. I mean, I'm not saying you shouldn't get out in the sun. I'm sure you should. But really I think therapeutically near infrared helmet would be the way to go.
Dan Pardi - 19:23: So all athletic teams that have the possibility of incurring some sort of concussion, it would be propitious to have a helmet like this on [crosstalk 00:19:32].
Michael Hamblin - 19:32: At least so, yeah. I mean a lot of the problem with a head injury is chronic, right? So you have concussion. Most people recover fine, but in some cases you end up with longterm psychological problems. Insomnia, irritability, headaches, and these lasts for months. And they are treated quite well with these near infrared helmets.
Dan Pardi - 19:56: I want to go back to these mechanisms a bit. What is a chromophore?
Michael Hamblin - 20:01: It's a molecule that absorbs light, so it has an absorption spectrum wavelengths we're talking about in the range in the near infrared, and you have a spectrophotometer. You can record the absorption spectrum so you can see the peaks. Obviously, hemoglobin is a red pigment in the blood, so the absorption spectrum of hemoglobin is known pretty well, and an absorbed spectrum mitochondria is also fairly well-known. If you isolate mitochondria, have a dark brown pellet. Most of the cell is colorless, but it's the little mitochondria that have to color.
Dan Pardi - 20:36: I've seen that there are no mechanisms that we know about that are contributing to the aging process that do not include the mitochondria as a part of that mechanism. On the show, it's been a theme for a while, how do we increase and improve and sustain mitochondrial health, and we live indoors 90% of the time always fully clothed. The amount of actual sunlight that we get is vastly reduced from a natural condition. You can imagine here that one of the problems of energetics of the body has to do with the lack of red light that is penetrating into the skin. To get a question, can natural red light penetrate clothing?
Michael Hamblin - 21:15: The longer the wavelength the better it penetrates clothing, so when you got to 900 nanometers clothing is pretty transparent. It's not like it's not a barrier, but it doesn't really absorb.
Dan Pardi - 21:29: There goes my idea for diaphanous clothing that people can walk.
Michael Hamblin - 21:32: I mean yeah, red light doesn't go through. With red light you're talking about what's the color of the dye in your clothing, right, so if you have a black T-shirt, red light's not going to go through. No.
Dan Pardi - 21:43: Mitochondria, and other parts of the cell on the body will absorb red light and it affects their physiology. We know that a variety of things occur including a burst of reactive oxygen species. We thought formerly that those were bad. We wanted to limit them. That was a big mistake. We now know that the induction of those through things like exercise and fasting and Xenohormetic molecules and food, that the triggering of those reactive oxygen species is important for our health. The triggers pro survival pathways, transcription factors that then elicit a variety of proteins that make the cell healthier.
22:19: Red light is one of these nutrients, if you will, or stimulators of that process and that potentially is why we are seeing a broad range of different issues benefit from red light therapy. So I'm really interested in looking at photobiomodulation just as a health practice. Health practice is what I define as the different things you can try to incorporate into your life willfully to try to be healthy.
22:45: We now have, as you mentioned, all different sorts of devices ranging from small to large that have different philosophies about the right wavelength and intensity. Can you see red light becoming a part of a regular thing that somebody who's looking to optimize their health should do to add one other stimulation for health?
Michael Hamblin - 23:04: Absolutely. I predict that day will come on every household will have at least one photobiomodulation device, and maybe they'll have several, have a helmet, will have something to wrap around their joints and their legs or on a big panel fairly a comfortably off. You may have a whole body light bed. This is no real downside of this. The side effects of very rare and very minor, but all intents and purposes, there are no side effects.
Dan Pardi - 23:38: I was going to ask, can you overdo it?
Michael Hamblin - 23:41: Well, in principle you can overdo it. I think you'd to be a bit crazy, you'd have to lie in a light bedtime for like two hours or you'd have to have a helmet on your head for an hour. These things are designed for treatment periods of 15 to 30 minutes because it's a bit boring to sit there for a huge length of time.
Dan Pardi - 24:04: Right.
Michael Hamblin - 24:04: One issue that not many people realize is that different individuals have different sensitivities. There is a small number of people who are hyper sensitive to light. They're ones that tend to complain of side effects and, "Oh, I couldn't get to sleep. I had a headache." Want to have that. I think it's fairly rare and also these people are hyper sensitive to all sorts of things. Bright lights, like smells, like all the people that say they are allergic to a lot in life.
24:36: And so as another small group of people that don't like blocks of wood, you could shine light on them all day and nothing would happen, but the majority of people are somewhere in the middle and the people that make recommendations for dosimetry are constantly trading on the bulk of people in the middle.
Dan Pardi - 24:55: Are these the frequencies of red and an infrared light that will warm up the body?
Michael Hamblin - 25:00: To some degree, the majority of the heat comes from the actual LEDs. So the electrical efficiency of the LED is around about 25, 30%, right? 70% of the electricity you put in is heat in the dials. So manufacturers make great efforts to remove this heat. They have fancy metallic conducting sort of things. A lot of devices will have fans, little fairly silent fans to circulate to remove the heat from the device.
25:36: Now, the radiation itself, when it's absorbed by the body will produce some heat. Well, that's the power density so they use that mild, but really it's a pleasant feeling of warm. You have to get up to several hundred million watts per square centimeter before the heat on the skin becomes uncomfortable. It's definitely not worth worrying what happens inside your body. If the intensity on the skin is painful, you'll go, "Ouch." People worry bullet [inaudible 00:26:07]. I think that'd be ridiculous. If you can't feel it on your head, it's not going to do anything nasty to your brain.
Dan Pardi - 26:18: I have an infrared sauna. The difference between me sitting in an infrared sauna and standing in front of a Joovv light is very different. The Joovv is a manufacturer, they make one of these devices. One that they make is the size of you. So it's about five or six feet. [crosstalk 00:26:32] The difference between standing in front of the Joovv, like you said, slightly warm and being in the infrared sauna where you sweat like crazy is that have everything to do with the frequency of the red light?
Michael Hamblin - 26:44: Absolutely. So infrared saunas do not generally have much near infrared. I mean some manufacturers are going to put near infrared LEDs and infrared saunas, but by and large that ceramic imaging plates that are a bit a broad band centered about nine microns, 9,000 nanometers. And it's a very broad band. So there is all the way down to one or two microns. Now, this has a physiological effect. Mainly the chromophores mid-infrared is water, that's the only conceivable chromophore, but there is special kinds of water inside cells called nanostructured water, which has different absorption properties from bulk water.
27:28: The hypothesis is that made in for add, maybe even near infrared can be absorbed by this nanostructured water and that can change the confirmation of ion channels for instance because the nanostructured water is on the membranes in which there are ion channels. So even at a relatively small amount of perturbation to the vibrational structure of the water could change the protein in the ion channel. That's the hypothesis.
Dan Pardi - 27:59: And that might affect energetics by making it perhaps [crosstalk 00:28:02].
Michael Hamblin - 28:04: That's why the calcium changes is mainly opening of calcium ion channel.
Dan Pardi - 28:09: So how close do you want to stand or be near one of these devices?
Michael Hamblin - 28:14: It doesn't have to be on your skin. I put it on my skin because I think it's more efficient. The LED is touching your skin more of the light goes in rather than being diffusely reflected. The LED light is not focused. So if you stand in front of an LED panel, a surprising amount of the light is diffusely reflected off your skin. To lie on the LED power, much more of it goes in.
Dan Pardi - 28:41: So the closer you are the more intense the light will be in terms of its absorption. You're getting more out of the time?
Michael Hamblin - 28:49: Yep. One thing I tell a lot of people is that LED light is cheap. You can have one or 200 watts of led light, but not a lot of money. So then you don't worry so much about wasting a lot of the light. If it just goes off into the room or it's reflected from the skin.
Dan Pardi - 29:07: You have longer exposures because you're in the room. It's less intense, but are getting exposed to red light in your day.
Michael Hamblin - 29:13: If you only have one or 200 milliwatts laser, I mean that's very little power so you get all of it into the area you're using, which is, yeah, not to say that laser therapy doesn't work. That's not a very efficient way of doing it.
Dan Pardi - 29:28: We know with circadian biology or timing biology, that blue light is the most potent signal, particularly for entering into the eye affecting what are called intrinsically photosensitive retinal ganglion cells that go to the master clock and tell the brain it's day. Blue light means it's day. Do you know of red lights... Does that have any effect on the circadian system, which then would mean that the timing of your exposure to red light being an important factor that we need to think around? Do you want to have this around Dawn and dusk? That's when the tone of natural light is more red or does it really matter? Is it just a certain amount of exposure per day that seems to do the trick?
Michael Hamblin - 30:11: In my understanding is you want the blue light in the morning. The blue light suppresses melatonin and wakes you up. Red light increase's melatonin and sends you to sleep, so you want the red light last thing at night before you go to bed and the blue light in the morning. That's my understanding. And red near infrared light is surprisingly good at sending you to sleep.
Dan Pardi - 30:33: Interesting. I did not know that. You can do this within let's say an hour before bed, and that should be enough to help you?
Michael Hamblin - 30:41: I have a near infrared device I keep by my bedside. If I happen to wake up in the middle of the night, I put it on my head and back to sleep like a baby.
Dan Pardi - 30:51: Is there direct evidence that red light will stimulate the production or synthesis or release of melatonin or is it simply just the absence of the blue light that's causing that?
Michael Hamblin - 31:00: There's a couple of papers. There was a Chinese paper where they used whole body red LED type things. I think they measured melatonin. This search one of the fitter by modulation terms. Honestly, the even so triple LT is still the best term to search for cognitive melatonin. You'll probably pick up a few references.
Dan Pardi - 31:24: I saw one of your recent references on photo biomics.
Michael Hamblin - 31:28: Right.
Dan Pardi - 31:29: Tell us about that.
Michael Hamblin - 31:30: So the idea is if you put light on the belly can you beneficially affect the composition or what microbiome and the guts. All the different bacteria that live in your gut have to be in a nice healthy balance. Right? A lot of the bacteria are beneficial, but it's quite easy for the non beneficial bacteria to take over it depending on what you're eating and other parts of your lifestyle.
31:59: People are realizing now that imbalances in the microbiome, mainly in the gut microbiome, but there are other important microbiomes on your skin and in your mouth and other parts of the body, but mainly the gut. So the folks in Australia have done some studies in mice by pushing red near infrared light on the belly and they've measured the bacteria in the feces and found beneficial changes. I don't think this has been done yet in humans. I'm sure people are trying it.
Dan Pardi - 32:33: Certainly the gut is an interesting subject, and one that I think maybe 15 years ago a few people were talking about. Now, it's appreciated and discussed so that is that another interesting attribute of red light. Can it enhance our own microbiome and create a more complimentary beneficial community or is it also having an effect on the endocrine system that they release by effecting their energetics?
Michael Hamblin - 32:56: If it is affecting the bacteria, what is the mechanism of action?
Dan Pardi - 33:00: Are you aware of any work looking at the combination of the compound, methylene blue and photobiomodulation? And for the audience, methylene blue is a very exciting compound. The national Institute of aging has the aging intervention program. They're looking at different compounds that have an influence on lifespan. One of the compounds that has had a positive effect extending rodent lifespan is methylene blue.
33:23: Old compound thought to be a mitochondrially targeted antioxidant. So instead of broadly quenching reactive oxygen species might work more specifically within the mitochondria to quench those free radicals and thereby having a beneficial effect on reducing DNA damage to mitochondrial DNA. Is there any work that you're aware of that's looking at that combo because they're both affecting energetics? Could this be just a combo?
Michael Hamblin 33:48: Methylene blue as you say it, is a very multifunctional dye, but it does act as a traditional photosensitizer in photodynamics therapy. And for that to happen, the light has to be absorbed by methylene blue, which has a broad absorption peak centered about 660 nano, 630, 660, 670 will be absorbed by methylene blue, which will then go to a triplet state and you will pass the energy to grand state oxygen producing reactive single oxygen. Now, we mentioned ROS before. These are ROS that are produced in the cell by the mitochondria.
34:27: In the case of the methylene blue, it's a federal chemical generation of ROS. It's possible low-levels of single oxygen can be beneficial. Certainly high levels kill things. They kill bacteria. They kill cancer cells. Traditional photodynamics therapy. Of course, you could use near infrared light, which is not absorbed by methylene blue. My understanding is that in the absence of light, methylene blue functions in the mitochondria as an alternative, electronic scepter actually participates in mitochondrial electron transfer.
Dan Pardi - 35:04: Right.
Michael Hamblin - 35:05: And that's why it helps, right, in disorders and so forth and so on. So if you were going to combine methylene blue with light, I would say carefully whether you want the light to be absorbed by the methylene blue, in which case you're doing very low dose PDT. You could use near infrared when it's definitely not absorbed by methylene blue. It could be absorbed by the mitochondria and then you could look to see if they were beneficial, even synergistic interactions. The other thing is when you ingest methylene blue systemically, it's reduced to the nuclear form. So it stops being blue and it doesn't absorb light.
Dan Pardi - 35:43: I will wait to see clinical outcomes before I start to muck around with that sort of combination. Last question for you. What is the area that you're most excited about? Is there momentum in a certain area at the moment
Michael Hamblin - 35:59: The two big areas are Alzheimer's and Parkinson's, which have no real medical treatment at all. As you probably know, tens of billions of dollars have been wasted on failed clinical trials for Alzheimer's. It really has been a graveyard for many pharmaceutical companies. Yeah, Parkinson's, likewise. And then psychiatric disorders. So again, it's a huge market and there's a lot of psychiatric drugs out there and some of them work, but most of them have fairly bad side effects. Antidepressants, sleeping pills.
36:38: I mean they make a lot of money, and obviously they work to some degree, but people are becoming more lows to take psychiatric drugs. And if a near infrared helmet could produce the same benefits or even better benefits than these drugs, I think huge enemy. But I think Alzheimer's is the single most exciting area. Nothing else works. There are rials going on now for photobiomodulation for Alzheimer's.
Dan Pardi - 37:06: It could possibly be working via multiple mechanisms.
Michael Hamblin - 37:11: I believe so. Yeah, and increases cerebral blood flow and oxygenation. So if nothing else, just having more blood and better oxygen delivery to your brain, it's helpful. All the transcription factors and neurogenesis and ectogenesis, all these other signaling pathways in your brain.
Dan Pardi - 37:29: Michael, this is such a fascinating subject. Quite honestly, I've been interested in life for a long time, and I've been in a way reserving my investigation in red light where I had enough time to go deep, the chance to speak with you, the lifetime achievement award winner from the society and photobiomodulation. It's such an honor. Thank you so much for your work and your time today. I'm excited to share this with our community.
Michael Hamblin - 37:53: Well, I've enjoyed talking to you.