Light as a Healing Modality and Natures Signaling

Using Light (Sunlight, Blue Light & Red Light) to Optimize Health (Huberman Lab Podcast #68)

Physics of light
 

Light is electromagnetic ENERGY.

Light travels through the environment in the form of waves. Energy can change the way that other things behave. It can cause reactions in the cells of our body.

Light has many different wavelengths.
Rainbow is just the visible for humans spectrum of light. Other animals can see infrared (snakes) energy. Ultraviolet light is invisible to us but it affects our health — our skin and even can reduce pain levels.

Different wavelengths can penetrate tissues to different depths:

● Longer wavelengths (red, infrared) penetrate through tissues. Even down to the bone marrow.
● Shorter wavelengths (blue, green, ultraviolet) don’t penetrate deep. (just beneath the top layer of skin).

Biology of light

If you had to imagine a real-world surgical tool by which to modulate our biology light would be the sharpest and the most precise of those tools.

Different wavelengths can impact mitochondria and the nucleus.
There are different pigments that absorb light. Certain pigments absorb particular wavelengths of light.
Every biological function of light has to do with absorbance or the reflectance of light or light passing through that particular thing.

3 main ways how we use light

1. Photoreceptors in eyes (rods & cones). Rods are very sensitive to even a few photons. Cones absorb red/green/blue wavelengths.
2. Skin pigment – melanin – absorbs UV light, which in turn creates a set of biological signals in skin cells, that in turn changes skin pigmentation (more/less melanin).
3. Every cell of our body feels the impact of light indirectly. Melanocytes of our skin and photoreceptors of our eyes take the light signals and then pass off a set of instructions to the other organs and tissues of your body

Use Cases & Tools

Light is a transducer (communicator) of what’s going on in the environment around you.

Blue light, UVB (UltraViolet B), and Sunlight (full spectrum)

Light at night

If you wake up in the middle of the night and flip on the lights and they are very bright fluorescent lights — your melatonin levels go from high to zero.
So if you need to turn on lights in the middle of the night — use the minimum amount of light required, long wavelengths (dim amber, dim red).
Also going from a dark room into a very brightly lit room immediately makes you feel very alert by releasing adrenaline.

💡 Tool 1: AVOID LIGHT AT NIGHT. IF YOU NEED IT, USE THE RED DIM LIGHT, AS DIM AS POSSIBLE


Light through the year

Light inhibits melatonin production.
The more light in the day — the less melatonin.
It is good for the summer months to have much light exposure.
In winter it makes sense to spend more time indoors. (but nevertheless, almost all people have too less sunlight exposure in winter).

😴 Melatonin:

1. Tends to make us more asleep.
2. Increases bone mass and growth hormone.
3. Has antioxidant and anticancer effects.
4. Too much melatonin decreases gonad function and decreases own melatonin production — don’t take it in supplements!

Light increases mating activities

The environment around us is converted into a signal that changes the environment within us.

Exposure to UV light to your skin and to your eyes increases testosterone and estrogen [1], what causes:

● increasing the desire to mate;
● enhancing female attractiveness by males;
● enhancing romantic passion in males and females — women focused more on increases in

physical arousal and sexual passion, whereas the men scored higher on the cognitive dimensions of passion, such as obsessive thoughts about their partner and so on.

💡 Tool 2: To increase testosterone and estrogen, mood, and feelings of passion — get 2-3 or more exposures per week of 20-30 minutes of sunlight onto as much of your body as you can reasonably expose it to.


Light and Vitamin D3

Light exposure to the skin is needed for vitamin D3 synthesis.
People who have darker skin need more sunlight exposure in order to activate the D3 pathway than do people with paler skin.
Why? Darker skin — more melanocytes — more light absorbed — less light goes to the D3 pathway synthesis.
💡 Tool 3: Get as much bright light exposure as you safely can in the morning and throughout the day for sake of both energy at day, sleep at night, enhancing mood, and regulating appetite.


Light decreases pain

Pain tolerance increases in long-day conditions, because of UVB exposure to the skin, and to the eyes (through the melanopsin cells and endogenous opioids). Some related articles:

● Levels of the brain and/or plasma corticotropin-releasing hormone (CRH), β -endorphin, ACTH and corticosterone (CORT) were enhanced by UVB. [2]
● Bright light treatment suppresses mouse nocifensive behaviors [3]

💡 Tool 4: If you’re somebody who’s experiencing chronic pain, provided you can do it safely, try to get some UVB exposure, ideally from sunlight. 20-30 minutes, 2-3 times a week.

Immune function

If we get more UVB exposure in our eyes — the spleen and immune function are enhanced, by activation of the sympathetic nervous system.
Also, more UVB exposure to the eyes triggers faster wound healing and hair growth, by activating stem cells in skin, hair, and nails. In these cases, exposure to the skin is also helpful.
Most people would do well to get more UVB exposure from sunlight throughout the entire year, provided they aren’t burning their skin or damaging their eyes in some way.
💡 Tool 5: For faster wound healing, and hair and nail growth — get more UVB exposure to the skin and in the eyes.

Mood

Avoid exposure to UVB light from artificial sources between the hours of 10 pm and 4 am, to prevent dopamine decrease and depression.
:bulb: Tool 6: If you want to keep your mood elevated and be motivated — get a lot of light UVB light throughout the day and avoid it at night.

Even on a cloud-covered day, you get far more light energy – photons – through the cloud cover than you are going to get from an artificial light source.
Don’t try to get your sunlight exposure through sunglasses or a windshield of a car — they filter out the UVB light.

💡 Tool 7: If you feel depressed in the winter months and there are no opportunities to get sunlight exposure — you can use a SAD lamp or LED lighting panel (930-1000 LUX).

Cardiometabolic function

Even dim light at night (100 lux), during only 1 night causes an increase in nighttime heart rate (by the overly active sympathetic system), decrease in heart rate variability, and increases in next morning insulin resistance [4].
💡 Tool 8: Always sleep in the dark. As dark as it is possible.


Red and Infrared light

Red and infrared light has this amazing ability to penetrate through tissues, maybe even to the bone and bone marrow.

Dermatology

Reduction in skin lesions, scars from acne, and acne lesions themselves [5, 6].
How? By low-intensity burning of the top layers of the skin and stimulating stem cells in lower layers of the skin, to produce new skin cells to replace that burned out on the top.
It also works in wound healing and removing some sorts of pigmentation.


Brain and Eyes health

2-3 min per day of 670-790 nm red light exposure from the safe distance of ~1 meter, in the first 3 hours of the day, causes in 40+ humans the improvement in visual function (acuity, up to 22%), by the reversal of the aging process of retina neurons and by reducing and reversing of the accumulation of drusen (cholesterol deposits in the eye retina).
💡 Interesting fact: Rods and cones of the neural retina use the most amount of ATP and energy in the entire body.


Red light for night shift workers

Red light (as dim as it’s possible) can be beneficial for night shift workers, to stimulate alertness [7].

Extra biohacking tool — brain health and function enhancement with the flashing lights

A pattern of flashing light (40 Hz) delivered to the eyes creates a pattern of neuronal firing (Gamma waves), that in turn triggers molecular pathways, that:

● reduce amyloid plaques and phosphorylated tau, which cause age-related cognitive decline;
● stimulate some pathways that lead to the enhancement of different neuronal functions.

More research is still needed on specific practical protocols for applying 40-hertz flashing lights, but there are already very promising results. [8].