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Weekly · Sunday Morning

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Rapamycin extends mouse lifespan 9–14%
NAD+ precursors reverse aging in humans
Blue-light glasses improve sleep quality
Walking 10 min after meals blunts glucose
Verdict change — caffeine half-life downgraded

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

Content›Video›Using Light (Sunlight, Blue …

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

Andrew Huberman2h 24m · 2022-04-18

Support Rate

79%

179 of 226 claims supported

Support rate

179 of 226 claims supported

179 supported47 partial / not

Claims from this content

179

✓Well SupportedAndrew Huberman drinks Athletic Greens twice a day, typically once in the morning and again in the afternoon or late afternoon, mixed with water and lemon or lime juice.✓Well SupportedVitamin K2 is important for calcium regulation and cardiovascular health.✓Well SupportedVitamin D3 is critical for metabolism, hormone function, and brain function, and most individuals do not get enough even with ample sunlight.✓Well SupportedAndrew Huberman finds Thesis nootropics, particularly Clarity and Energy formulas, to be a 'total game changer'.✓Well SupportedBright light, particularly blue light, suppresses melatonin production; high exposure during the day and minimal exposure at night is beneficial.

More from Andrew Huberman

Andrew Huberman on Creatine

Huberman X thread: creatine and aging

Andrew Huberman on Morning Sunlight

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A. Volkovreader

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Bookmarking — the dossier-vs-overview split is the right call. Most of the time I want overview; sometimes I want receipts.

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✓Well SupportedExposure to short-wavelength UV blue light can increase testosterone and estrogen levels and the desire to mate.

✓Well SupportedElectrolyte drinks with sodium, magnesium, and potassium without sugar are important for optimal brain and body function and hydration.

✓Well SupportedDim red light at night promotes alertness without inhibiting melatonin production or increasing cortisol.

✓Well SupportedGetting bright light exposure in the morning and throughout the day is recommended for improving sleep, energy, mood, and regulating appetite.

✓Well SupportedExposure to dim light during sleep can negatively disrupt morning blood glucose levels.

✓Well SupportedDuring shift work, use as much light as safely possible when alertness is required and darkness for sleep.

✓Well SupportedApproximately two hours of daily skin exposure to sunlight on the upper body, arms, neck, and face can lead to significant increases in testosterone and estrogen.

✓Well SupportedAvoiding bright light exposure to the eyes between 10:00 PM and 4:00 AM can help maintain dopamine levels.

✓Well SupportedCertain wavelengths of light can be used to treat medical conditions, as evidenced by phototherapy for lupus.

✓Well SupportedIndividuals suffering from low mood or depression should be especially careful to avoid UVB exposure from artificial sources, particularly from 8:00 pm to 4:00 am.

✓Well SupportedGetting sunlight in the eyes early in the day, when the sun is low and the UV index is low, is a safe time for sun exposure.

✓Well SupportedThe eyes are extensions of the brain outside the cranial vault.

✓Well SupportedGoing outside, even on a cloudy day, provides significantly more photon energy than typical indoor lighting, aiding circadian clock setting.

✓Well SupportedUVB light exposure to the eyes enhances spleen function and immune response by activating the sympathetic nervous system.

✓Well SupportedNear-infrared light at 839 nm may increase mitochondrial function and ATP production.

✓Well SupportedRed light exposure early in the day helps metabolically active cells in the back of the eye replenish ATP production.

✓Well SupportedPhototherapy, including red and near-infrared light, benefits cellular processes involving mitochondria beyond skin cells.

✓Well SupportedIndividuals with darker skin pigmentation require significantly longer sun exposure to produce the same amount of vitamin D compared to those with lighter skin.

✓Well SupportedPrescription lenses and contacts are acceptable to wear when viewing sunlight for circadian rhythm setting.

✓Well SupportedViewing sunlight through a window takes approximately 50 times longer to activate the circadian system compared to direct outdoor exposure.

✓Well SupportedMelatonin inhibits gonadotropin-releasing hormone, luteinizing hormone, and hormone production, and is the hormone of darkness.

✓Well SupportedSunlight exposure is necessary for the synthesis and function of vitamin D3 in the body.

✓Well SupportedHuman hormonal responses, such as changes in melatonin, testosterone, and estrogen, are entrained to the external light-dark cycle and change as day length varies.

✓Well SupportedThe increase in reproductive hormones and mating desire triggered by light exposure is mediated by skin, not eye, exposure to specific wavelengths.

✓Well SupportedMelanopsin-containing retinal ganglion cells project to brain areas like the habenula, influencing mood by affecting dopamine and serotonin release or suppression.

✓Well SupportedAvoiding UVB light exposure from artificial sources between 10 p.m. and 4 a.m. can prevent activation of the eye-to-perihabenular pathway, which can lead to depression.

✓Well SupportedSeeking sunlight exposure, even on cloudy days, is beneficial.

✕Not SupportedWearing blue blockers all day, especially in the morning and daytime, is a disservice because windows filter out UVB light.

✓Well SupportedExposure to bright light increases alertness by triggering adrenaline release via the eyes to the brain stem's locus coeruleus.

◐Partially SupportedThesis nootropics are designed for specific outcomes targeting particular neural circuits and brain functions.

◐Partially SupportedLight exposure on skin and eyes can indirectly influence the function of deep organs like the spleen.

◐Partially SupportedDuring summer and spring, individuals should aim for more sunlight exposure to ensure proper melatonin signaling aligned with the time of year.

✓Well SupportedUsing long wavelength light, such as red or amber light, in the middle of the night is less likely to reduce melatonin production unless it is very bright.

◐Partially SupportedRed light and near-infrared light can enhance neuronal function, including in vision and cognition.

◐Partially SupportedCortisol levels are increased in major depression, with a signature pattern of a late-day release.

◐Partially SupportedRed light therapy with 670nm light for 3 minutes daily improved color vision.

◐Partially SupportedWound healing is faster with sufficient UVB exposure.

◐Partially SupportedRed light has been shown to be beneficial for mitochondria in skin cells, reducing reactive oxygen species and improving mitochondrial function.

✓Well SupportedUVB exposure to the skin and eyes can reduce the perception of pain.

✕Not SupportedWearing blue-blocking glasses during the day is counterproductive as bright light is beneficial for circadian rhythm and alertness.

◐Partially SupportedExposure to red light for therapeutic purposes should occur early in the day, within the first three hours of waking.

◐Partially SupportedRed light, when appropriately dosed and delivered, can penetrate cells, access mitochondria, and increase ATP production.

◐Partially SupportedTo safely use 670nm and 790nm light for neuronal function, position the light source at a comfortable distance that does not cause squinting or physical discomfort.

◐Partially SupportedRed light (around 670nm) and near-infrared light can improve visual function in individuals aged 40 and older.

◐Partially SupportedViewing red light (670nm) for 2-3 minutes daily for up to 12 weeks resulted in a 22% improvement in visual acuity in individuals aged 40-72.

◐Partially SupportedLight entering the eyes through eyelids during sleep can activate cells that increase sympathetic nervous system activation and disrupt metabolism.

◐Partially SupportedSufficient estrogen levels are important for optimal sexual function in men, in addition to testosterone.

✕Not SupportedAvoid looking directly at painfully bright light sources, whether artificial or sunlight.

◐Partially SupportedSAD lamps or inexpensive LED lighting panels (930-1000 lux) can be beneficial for individuals experiencing a drop in energy or increased depression during winter months.

◐Partially SupportedUVB light exposure to the eyes can benefit mood, hormone pathways, and pain reduction.

◐Partially SupportedExposure of melanopsin-containing ganglion cells to UVB light is critical for triggering stem cell turnover in skin, hair, and nails.

◐Partially SupportedSunlight exposure on the skin, without causing damage, is likely beneficial for health, particularly during winter.

◐Partially SupportedGetting UVB exposure onto the skin is beneficial for the vast majority of people.

◐Partially SupportedThe headache and squint reflex triggered by bright light can serve as a useful guide for determining safe light exposure distance and intensity.

◐Partially SupportedRed light therapy sources should not be so bright as to cause pain or discomfort when looking at them.

◐Partially SupportedIncreased proliferation and self-renewal of cells and tissues in the body occur with sufficient UVB light exposure to the eyes and skin.

◐Partially SupportedRed light therapy reduced reactive oxygen species and reversed neuronal aging in retinal cells.

◐Partially SupportedNeurons within the retina are the most metabolically active cells in the body, requiring adequate blood flow for energy and nutrients.

◐Partially SupportedArtificial light stimulation of the eyes in the middle of the night negatively impacts the visual system.

◐Partially SupportedMelanocytes in the epidermis create skin pigmentation and respond to UV light exposure by increasing pigmentation.

◐Partially SupportedAs cells age, they accumulate reactive oxygen species, which leads to decreased ATP production.

◐Partially SupportedHair growth rate is faster in longer days, triggered by UVB exposure to both skin and eyes.

◐Partially SupportedRed and near-infrared light can penetrate deeper skin layers to alter the metabolic function of cells like sebaceous glands and stem cells.

◐Partially SupportedRed light can be beneficial when used late in the day or in the middle of the night, particularly for shift workers.

◐Partially SupportedDifferent wavelengths of light penetrate tissues to varying depths, with biological functions dependent on light absorbance, reflectance, or passage through cells.

◐Partially SupportedUVB light treatment can increase romantic passion and desire to mate in both males and females.

◐Partially SupportedShort wavelength light, such as blue, green, or ultraviolet light, does not penetrate tissues easily.

◐Partially SupportedSeeking UVB exposure from sunlight throughout the year is advisable, provided skin is not burned and eyes are not damaged.

◐Partially SupportedExposing subjects to 40 Hz light flicker can entrain the brain to match these patterns, increasing gamma oscillations in various brain regions.

◐Partially SupportedIn shorter days (winter), there is less light, leading to a longer duration of melatonin release; in longer days (summer), there is more light, leading to a shorter duration of melatonin release.

◐Partially SupportedUse the minimum amount of light necessary for safety when getting up in the middle of the night to avoid disrupting melatonin signaling.

◐Partially SupportedPit vipers can sense infrared energy emitted by warm-blooded bodies, which humans cannot see without special equipment.

◐Partially SupportedLight can target specific locations within cells, organelles, and organs to modulate biology.

◐Partially SupportedDuring deep sleep, the body naturally transitions through ketosis-like states and gluconeogenesis.

◐Partially SupportedViewing red light and near-infrared light daily can reverse the aging process of neurons.

◐Partially SupportedBright light exposure in the middle of the night powerfully inhibits melatonin production.

◐Partially SupportedNeurons require sodium to function, and many people can benefit from increased sodium intake if balanced with potassium and magnesium.

◐Partially SupportedLight powerfully modulates melatonin, typically by shutting it down, which is crucial for regulating bodily functions.

◐Partially SupportedThe total amount of skin exposure to sunlight determines the pattern and activation of biological signaling.

◐Partially SupportedWhite light contains all visible wavelengths, and sunlight includes visible and non-visible wavelengths that can impact the brain and body.

◐Partially SupportedReactive oxygen species are involved in redox signaling and can alter gene expression.

◐Partially SupportedGamma brain activity can be restorative for learning and memory and may help clear debris and reduce age-related cognitive decline.

◐Partially SupportedLooking at red light panels for 2-3 minutes daily for two weeks may improve neuronal function in individuals over 40.

◐Partially SupportedCognitive sharpness declines with age, and preserving neuronal function is beneficial.

◐Partially SupportedPain tolerance increases in longer day conditions, mediated by UVB exposure.

◐Partially SupportedUVB light exposure increases beta-endorphin release, acting as an endogenous painkiller.

◐Partially SupportedBright light treatment can activate a visual circuit involving the periaqueductal gray area to produce antinociceptive effects via endogenous opioids.

◐Partially SupportedBlue blockers block short-wavelength UVB light, which is necessary for retinal and skin exposure to achieve biological effects on hormones and pain reduction.

◐Partially SupportedIncreases in testosterone and estrogen likely drive psychological changes related to sexual passion and desire to mate, with a bidirectional interaction between hormones and psychology.

◐Partially SupportedHuman data on red light and other wavelengths for ovarian and testicular health, including improving testosterone output, is not yet clear.

◐Partially SupportedCircannual rhythms use hormone levels to track the 365-day year, influenced by environmental light exposure.

◐Partially SupportedExposure to UVB light rapidly activates systemic neuroendocrine responses, including the release of corticotropin hormone and beta-endorphins.

◐Partially SupportedIncreased p53 activity in skin keratinocytes is required for downstream increases in ovarian size, testicular size, testosterone, and estrogen.

◐Partially SupportedA study protocol involved 20-30 minutes of midday sun exposure equivalent to skin exposure to UVB light.

◐Partially SupportedUVB exposure to the eyes can be beneficial for mood, hormone pathways, and pain reduction.

◐Partially SupportedMelatonin influences the central nervous system to regulate wakefulness and sleepiness, associating it with the dark phase of the 24-hour cycle.

◐Partially SupportedThe anti-cancer and antioxidant effects of melatonin are mediated by the natural rise and fall of its signal across a 24-hour cycle and seasonal duration changes, not by artificially increasing melatonin levels.

◐Partially SupportedEndogenous melatonin can suppress the maturation of gonads, including reducing sperm production, testosterone production, and egg maturation.

◐Partially SupportedMelatonin levels rise in the evening towards sleep and continue to increase for several hours into the night.

◐Partially SupportedMelatonin regulates sleep-wake cycles, puberty timing, gonadal function, and bone mass.

◐Partially SupportedIndividuals with certain eye or skin conditions should consult specialists before increasing UVB exposure.

◐Partially SupportedThere is limited data supporting mechanistically-backed effects of whole-body illumination with infrared saunas on skin quality or repair.

◐Partially SupportedMelatonin possesses potent antioxidant and anti-cancer properties.

◐Partially SupportedIntrinsically photosensitive ganglion cells (melanopsin cells) in the eyes absorb short-wavelength light and communicate with the pineal gland, influencing melatonin release.

◐Partially SupportedEndogenous melatonin positively impacts bone mass by stimulating osteoblast production and has antioxidant and potential anti-cancer effects.

◐Partially SupportedIncreased light exposure leads to less melatonin and more hormone output from the gonads.

◐Partially SupportedLight exposure can change gene expression throughout the lifespan.

◐Partially SupportedDimming lights or turning them off can bypass some inhibitory effects of light on melatonin production.

◐Partially SupportedCalories in food are a measure of energy, indicating how much heat it generates when burned and thus how much energy it can provide the body.

◐Partially SupportedBaseline hormone levels were measured in human subjects after they avoided sunlight and covered up for a few days.

◐Partially SupportedThe absorbance and reflectance properties of a surface determine whether light energy is absorbed and impacts that location or bounces off.

◐Partially SupportedCones in the eyes have three main varieties (long, medium, and short wavelength absorbing photopigments) that allow for color perception.

◐Partially SupportedThe body has different optimal functions during winter and summer.

◐Partially SupportedLight energy is converted into biological signals by the absorption of light by pigments.

◐Partially SupportedLight therapies involving localized application without eye involvement are likely less potent than systemic activation of larger skin areas and the eyes.

◐Partially SupportedUV light can burn skin and may positively impact the body, potentially reducing pain perception.

◐Partially SupportedHigh-intensity light therapies for skin modification involve controlled burning of the epidermis to trigger stem cell renewal.

◐Partially SupportedThe photic avoidance pathway can trigger headaches and squint reflexes in response to excessively bright light.

◐Partially SupportedInterventions to reverse cellular aging aim to increase ATP, reduce reactive oxygen species, and disrupt aging pathways.

◐Partially SupportedLow-level light therapies, including red and near-infrared light, can treat dermatologic issues such as acne and scarring.

◐Partially SupportedSystemic effects from broad light and eye exposure combined with local treatments are most likely to yield successful outcomes.

◐Partially SupportedLight impacts biology through direct pathways, such as on the skin, or indirect pathways involving relayed signals.

◐Partially SupportedDuring winter, spending more time indoors is advisable, but morning and daytime bright light exposure can offset seasonal mood changes.

◐Partially SupportedLow-level light therapies often involve red light and near-infrared light.

✕Not SupportedApplying high-intensity light technologies directly to the eyes can damage retinal and other eye tissues.

◐Partially Supported40 Hz light stimulation delivered to the eyes has been shown to reduce amyloid plaques and phosphorylated tau.

◐Partially SupportedProtocols for using flickering lights to enhance focus, sleep transition, and offset neurodegeneration are expected to emerge soon.

◐Partially SupportedUVB light exposure, from sunlight or artificial sources, increases pain tolerance.

◐Partially Supported40-hertz flickering light is being explored for Alzheimer's and dementia.

◐Partially SupportedLooking at 40 Hz flickering light is generally safe but can induce seizures in individuals prone to epilepsy.

◐Partially SupportedUVB exposure and red light therapy are potent methods for increasing wound healing and skin health.

◐Partially SupportedLow-level light therapy with infrared light is effective for treating acne and other skin lesions, reducing scars, and decreasing new acne cysts.

◐Partially SupportedCommercially available red light panels often combine red and near-infrared light, may be too bright for direct eye exposure, and may include eye protectors.

◐Partially SupportedLight impacts biology at the endocrine, neuronal, and immune levels, as well as mood, through illumination of the eyes, skin, and other tissues.

◐Partially SupportedEnergy, including light energy, can cause reactions in cells and influence biological processes.

◐Partially SupportedPhototherapy, like 40 Hz gamma entrainment, demonstrates light's powerful local and systemic effects on cellular electrical and chemical outputs.

◐Partially SupportedPositive effects of red light and low-level light therapies are primarily from directed illumination of specific skin areas needing repair, not whole-body application.

◐Partially SupportedLight can influence biology through rapid, moderately fast, and slow, long-lasting effects.

◐Partially SupportedThe biological pathway of retinoic acid is similar to the natural pathway where photopigments in the eye convert light.

◐Partially SupportedLong wavelength light, such as red light and near-infrared light, can penetrate deep into tissues, potentially reaching bone marrow.

◐Partially SupportedAcne can sometimes become resistant to low-level light therapy, with initial improvements disappearing despite continued treatment.

◐Partially SupportedThe skin functions as an endocrine organ, producing and influencing hormones.

◐Partially SupportedSunlight exposure, particularly UVB, is associated with increased testosterone levels.

◐Partially SupportedUVB light exposure to the skin increases p53 activity in keratinocytes, which is required for downstream increases in ovarian size, testicular size, testosterone, and estrogen.

◐Partially SupportedUVB light exposure to the skin enhances follicle growth and maturation, indicating increased production of healthy eggs.

◐Partially SupportedSleeping in a room with 100 lux of overhead lighting impairs cardiometabolic function compared to less than 3 lux.

◐Partially SupportedSunlight exposure to the eyes can enhance mood.

◐Partially SupportedA 22% improvement in visual acuity, as measured by the Tritan exam, is considered a highly significant result in vision testing.

◐Partially SupportedUVB light exposure can reduce pain perception by activating endogenous opioid pathways.

◐Partially SupportedRed and near-infrared light are absorbed by all photoreceptors in the eye.

◐Partially SupportedRetinal rods and cones tend to accumulate significant reactive oxygen species (ROS) with age due to their high metabolic activity.

◐Partially SupportedUVB exposure from artificial lights throughout the day, especially in the morning, is generally insufficient for optimal health benefits like mood and energy.

✕Not SupportedUVB exposure from artificial sources at night can negatively impact sleep and energy levels by suppressing melatonin.

✕Not SupportedMelatonin is a powerful modulator of placental development and should be used with extreme caution during pregnancy, requiring consultation with a doctor.

✕Not SupportedCaution is advised regarding melatonin supplementation due to its potent effects on cardiovascular function, immune function, anti-cancer properties, bone mass, and gonadal function.

✕Not SupportedThe levels of melatonin in most supplements are super-physiological and too high.

✕Not SupportedWidespread use of melatonin, especially at high doses found in most supplements, is concerning given its powerful effects.

✕Not SupportedRepeatedly exposing oneself to bright lights during nighttime awakenings disrupts the brain's temporal information signaling.

◐Partially SupportedSystemic effects like hormone increases, pain reduction, and immune status improvement are downstream consequences of illuminating large skin areas and providing adequate UVB exposure to the eyes.

◐Partially SupportedGamma waves are a pattern of neuronal firing that clears aging-associated debris and enhances neuronal youthfulness.

◐Partially SupportedLight acts as a transducer communicating environmental information to the body.

◐Partially SupportedMaintaining healthy neurons is critical for visual system function and memory, as new brain cells are not significantly accumulated with age.

◐Partially Supported40 Hz light stimulation upregulates biological pathways that enhance neuronal function and maintain synapses.

◐Partially SupportedRed light exposure early in the day, within three hours of waking, can improve neuronal function.

◐Partially SupportedIncreased sodium intake, when balanced with potassium and magnesium, can lead to clearer thinking, better exercise recovery, and more energy.

◐Partially SupportedThe amount of daily light exposure, varying with seasons and hemisphere, influences circannual rhythms.

◐Partially SupportedSunscreen may block the beneficial effects of UVB light on p53 activation and downstream hormone increases.

◐Partially SupportedDifferent wavelengths of light can be absorbed by particular organelles within cells, such as mitochondria or the nucleus.

◐Partially SupportedRed light and near-infrared light therapies can reduce or reverse the accumulation of drusen in the eye.

◐Partially SupportedProbiotics are crucial for immune system and brain function.

◐Partially SupportedMelanocytes absorb specific wavelengths of UV light, triggering biological signals that alter skin pigmentation.

◐Partially SupportedRed light therapy may reduce cholesterol deposits and reactive oxygen species to improve neuronal function.

◐Partially SupportedBlue light (460nm) is more likely to suppress melatonin and increase wakefulness at night compared to red light (670nm) or dim white light.

◐Partially SupportedBlue blockers can be useful in the evening and nighttime for individuals experiencing issues with falling and staying asleep.