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Using Light (Sunlight, Blue Light & Red Light) to Optimize Health

Episode 68 Apr 18, 2022 2h 19m 18 insights
I describe the mechanisms by which different wavelengths of light impact the cells, tissues and organs of the human body, and how specifically timed light exposure of specific wavelengths can be used to improve sleep, enhance alertness, modulate hormone levels, and improve mood. I also explain the use of ultraviolet and infrared phototherapies to relieve pain increase testosterone and estrogen levels; improve skin health, appearance and wound healing; and how red light can be used to offset age-related vision loss and provide neuroprotection. Throughout the episode, I describe the mechanisms of light-based therapies and actionable tools that people can use positively impact mental and physical health. For the full show notes, visit hubermanlab.com.
Actionable Insights

1. Sleep in Total Darkness

Ensure your sleeping environment is completely dark (less than 3 lux), as even dim light exposure during sleep can disrupt autonomic nervous system function, increase nighttime heart rate, decrease heart rate variability, and increase next-morning insulin resistance.

2. Limit Nighttime Bright Light

If you must wake up in the middle of the night, use the minimum amount of light necessary to safely navigate, especially between 10 PM and 4 AM, to avoid plummeting melatonin levels and disrupting your body’s fundamental timekeeping signal.

3. No Late-Night Artificial UVB

Avoid exposure to artificial UVB light sources between 10 PM and 4 AM, and ideally from 8 PM, especially if you experience low mood, as this can reduce dopamine output and potentially worsen depression.

4. Maximize Daily Sunlight Exposure

Seek daily sunlight exposure to your eyes and skin, even on cloudy days, as it provides significantly more beneficial light energy than indoor sources; avoid sunglasses, hats, and blue blockers during this time, and never look at light so bright it’s painful.

5. Skin UVB for Hormones

Expose as much skin as reasonably possible to midday sun (UVB light) for 20-30 minutes, 2-3 times per week, for several weeks, to increase testosterone and estrogen, enhance romantic passion, and improve fertility by activating a P53 pathway in skin cells.

6. UVB for Pain Reduction

To increase pain tolerance, aim for 20-30 minutes of UVB exposure (ideally from sunlight) to both your skin and eyes, two to three times per week, as this triggers the release of endogenous opioids.

7. UVB for Skin & Hair Renewal

Ensure sufficient UVB light exposure to both your eyes and skin to accelerate wound healing, promote faster hair and nail growth, and enhance skin cell turnover for a more youthful appearance.

8. Winter UVB for Immunity

During winter months, prioritize UVB light exposure (from sunlight or appropriate artificial sources) to enhance spleen function and activate the sympathetic nervous system, thereby boosting immune system readiness to combat infections.

9. Red Light for Vision

For individuals 40 years or older, expose your eyes to red light (670 nanometers) for 1-3 minutes early in the day, a few times per week, to offset age-related vision loss by improving ATP production in retinal cells.

10. Nighttime Red/Amber Lighting

If you need light at night, use dim amber or red light sources, as these long wavelengths are less likely to inhibit melatonin production compared to short wavelength light, helping to maintain healthy sleep-related hormone levels.

11. Dim Red Light for Night Alertness

When needing to stay awake late at night for shift work or other activities, use dim red light sources to promote alertness without disrupting melatonin production or increasing cortisol levels.

12. Localized Red Light for Skin

Apply red light and near-infrared light therapy to localized skin areas to reduce acne, diminish scars, improve skin quality, and remove unwanted pigmentation by enhancing mitochondrial function and reducing reactive oxygen species.

13. Winter Bright Light Therapy

During winter months, if experiencing low mood or energy, use a SAD lamp or a 930-1000 lux LED lighting panel on your desk throughout the day to provide bright light exposure and improve mood.

14. Exercise Melatonin Supplement Caution

Exercise extreme caution with melatonin supplementation, especially at the high doses found in most over-the-counter products, as it is a powerful hormone that can disrupt natural physiological rhythms and impact various bodily functions.

15. Daily Nutritional Supplementation

Consider taking an all-in-one vitamin, mineral, and probiotic drink like Athletic Greens once or twice a day to cover basic nutritional needs, address deficiencies, and support microbiome health, along with Vitamin D3K2 for overall brain, body, and cardiovascular function.

16. Electrolyte Intake for Hydration

Dissolve one packet of Element (electrolytes without sugar) in 16-32 ounces of water first thing in the morning and during physical exercise to ensure proper hydration and electrolyte balance, which is critical for optimal brain and body function.

17. Meditation & NSDR Practice

Utilize meditation apps like Waking Up for various meditation programs, mindfulness training, or Non-Sleep Deep Rest (NSDR) protocols to explore different brain states and restore cognitive and physical energy, even with short 10-minute sessions.

18. 40 Hz Light Flicker for Brain

(Caution: This is preliminary research in clinical trials and may induce seizures in those prone to epilepsy.) Exposing eyes to 40 Hz flickering light may induce gamma oscillations in the brain, potentially reducing amyloid plaques and tau, and enhancing neuronal function to offset age-related cognitive decline.