Most People Are Vitamin D Deficient — But the Pill Isn't the Answer
Almost everyone today has been told they're vitamin D deficient. The standard recommendation is to take a supplement. But here's what most practitioners don't tell you: vitamin D in pill form is not the same as what your body makes from the sun — and the supplement form may carry risks that are rarely discussed.
Cholecalciferol — sold as vitamin D3 — was registered in 1984 as a rodenticide (rat poison). The same compound that kills rodents via hypercalcemia (toxic calcium overload) is what is in most vitamin D supplements, at far smaller doses. Whether those smaller doses cause cumulative harm over years of daily use is a question that has not been adequately studied.
Research has found that supplemental vitamin D does not produce the same cardiovascular benefits as sun-derived vitamin D. A randomized controlled trial found that sunlight exposure improved lipid profiles in vitamin D deficient men significantly better than supplementation.
What Sunlight Actually Does for the Body
The sun delivers far more than vitamin D. Sunlight triggers a cascade of biological processes — many of which cannot be replicated by a supplement. Research confirms the following benefits of regular, non-burning sun exposure:
The Nitric Oxide Mechanism
One of the most remarkable findings in sunlight research: UV light triggers the release of nitric oxide stored in the skin — a vasodilator that directly lowers blood pressure and improves blood flow throughout the cardiovascular system. This effect happens independently of vitamin D production and cannot be replicated by any supplement.
This is part of why countries at higher latitudes — less annual sun — have statistically higher rates of heart disease. It's not just vitamin D levels. It's the full-spectrum benefit of light on the skin.
The Hidden Risk of Sun Avoidance
The medical community's decades-long fear campaign around sun exposure may itself be causing harm. A Swedish study tracking nearly 30,000 women for 20 years found that those who avoided the sun had a mortality rate two to three times higher than those with the most sun exposure. The risks of sun avoidance were comparable to smoking in terms of overall mortality.
Additionally, a large review found that low sun exposure was associated with a range of serious conditions including certain cancers, multiple sclerosis, diabetes, cardiovascular disease, autism, and Alzheimer's disease.
Building Your Solar Callus
Your skin adapts to sun exposure the way your feet adapt to walking barefoot — through gradual conditioning. The "solar callus" is the term for a skin that is prepared for sun rather than shocked by it. Building it protects against burning while maximizing the biological benefits of light.
Set aside 6 weeks to build your solar callus by following this protocol:
- 1.See the sunrise every morning with bare skin (no sunscreen, lotions, or makeup) and bare eyes (no glasses or contacts). The first morning light — before the UV index rises — sets your circadian clock and begins photobiological signaling.
- 2.Use the DMinder app to track when UV levels in your location are sufficient for vitamin D production. Some northern latitudes cannot produce vitamin D from the sun in winter months — build your levels aggressively in summer.
- 3.Expose as much skin as possible during the vitamin D production window — without sunscreen. Start with short exposures and extend gradually as your skin adapts.
- 4.If you turn pink, stop — go into shade, then return for sunset. Burning is the threshold to stay below. The goal is regular, consistent exposure — not marathon sessions.
- 5.Eat vitamin C-rich whole foods before and during longer sun sessions to support the skin's antioxidant defenses. Bell peppers, citrus, papaya, kiwi, strawberries, and broccoli are the richest sources. Food — not a supplement. Isolated ascorbic acid in supplement form is a fraction of the full vitamin C complex found in whole foods.
When Sunlight Isn't Available: Real Options
- ●A Sperti Vitamin D lamp (UV-B specific) provides a sun-comparable signal for vitamin D production through the skin — not a supplement, but a light source that mimics the sun's mechanism
- ●A trip to a location below latitude 27° for a few weeks can meaningfully build vitamin D stores through the skin
- ●Whole food dietary sources: wild sardines, mackerel, herring, pasture-raised egg yolks, grass-fed beef liver, and UV-exposed mushrooms — vitamin D in its natural food matrix with co-factors intact
- ●Minimizing non-native EMF and blue light exposure helps maintain higher baseline vitamin D signaling year-round
Your Body Is a Solar Panel — Not a Calorie Calculator
One of the most overlooked explanations for weight that does not respond to diet or exercise is this: the body is a light-harvesting system. When photon input drops, the body does what every solar-powered system does — it expands its collection surface.
It gets bigger.
The Mechanism Is Not a Metaphor
- • Melanin is a photoreceptor — not just a pigment. It captures photons and converts light energy into biological signals. The entire melanin-producing system of the skin is part of the body's light-sensing and light-response architecture.
- • Fat cells are photosensitive — adipocytes express the same opsins (light-sensitive proteins) found in the eye: OPN2, OPN3, and OPN5. Your subcutaneous fat is not inert storage. It is light-responsive tissue.
- • Subcutaneous fat conducts light — research shows subcutaneous fat acts as a fiber-optic medium, transmitting photons from the skin surface to deeper tissues and mitochondria below. The fat layer is part of the photonic delivery system.
- • When light drops, collection surface increases — this is not a disease process. It is biology. When the signal drops, the receiver gets bigger. The body is doing exactly what it was designed to do.
Seasonal Biology — The Mammalian Blueprint
Every mammal that lives through winter understands this cycle. In the autumn, as day length shortens and photon input drops, mammals gain weight. In the spring, as light returns, they lose it. This is not a caloric phenomenon — food intake often stays roughly constant. The signal driving the shift is photonic, not caloric.
The trigger is the change in the light environment — specifically, the ratio of light to dark, the spectrum of available light, and the timing of light exposure relative to the circadian clock.
For wild mammals, summer always comes. They return to the light.
The Permanent Artificial Winter
Modern humans have built a light environment that mimics permanent winter:
- • Indoors for most daylight hours — light levels 50–500 lux instead of the 10,000–100,000 lux of outdoor daylight
- • Screens and artificial lighting dominant — heavy in blue, absent in near-infrared and full-spectrum
- • Morning light missed — the critical photobiological signaling window (sunrise through 10am) bypassed
- • No skin exposure — clothing, glass, and sunscreen block the photons that drive the biological signal
The body reads this as: the light is gone. Winter is here. Expand the collection surface and wait.
For most modern humans, summer never comes.
Lights Out — What the Research Has Documented
T.S. Wiley and Bent Formby's book Lights Out: Sleep, Sugar, and Survival laid out a compelling case decades ago: artificial light extension, disrupted sleep timing, and loss of the dark phase of the circadian cycle are the primary drivers of the modern obesity and metabolic disease epidemic — not calorie excess. The mechanism they described is hormonal and photobiological, not arithmetic.
The research since has strengthened this case. Shift workers have dramatically higher rates of metabolic disease, obesity, and cancer — not because they eat differently, but because their light environment is permanently disrupted. Light at night is now classified by the IARC as a probable human carcinogen (Group 2A). The sleep-weight-light connection is not fringe biology. It is documented.
The Prescription: Real Light, Not a Pill
No weight loss drug addresses photon deprivation. No calorie deficit addresses it. The intervention is light itself.
- • Morning sunlight on skin and eyes — daily, in the hours when UV index is building; this is the most powerful signal the body receives to reset circadian rhythms and photobiological function
- • Bare skin in midday sun during the solar callus building process — the photons must reach the photosensitive tissue; glass, sunscreen, and heavy clothing block the signal
- • Block artificial light at night — 550nm+ amber lenses after sunset; eliminate blue and white light sources in the hours before sleep; restore the dark phase of the circadian cycle
- • Not vitamin D supplements — an isolated pharmaceutical compound does not replicate the photonic signal. It bypasses the pathway entirely and introduces its own risks.
The person who cannot lose weight despite doing everything right is often correct — the framework being used to explain their body is the problem. The body is not broken. It is responding to its light environment exactly as designed. Change the light environment, and the biology changes with it.
The Long-Term Damage of Vitamin D Supplementation
The supplement industry has positioned vitamin D as a simple fix. The long-term picture is more complicated — and the damage can take years to reverse.
What Long-Term Vitamin D Supplementation Can Do:
- • Calcification of soft tissue — supplemental vitamin D drives calcium into soft tissue rather than bone when the proper regulatory balance is disrupted; calcification of arteries, kidneys, tendons, ligaments, and fascia is documented; some researchers believe that much of what we see as cellulite — hardened, dimpled subcutaneous tissue — is in part calcium deposition driven by chronic excessive vitamin D supplementation combined with mineral imbalance
- • Kidney damage — hypercalcemia (elevated calcium in the blood from excessive vitamin D) causes kidney stones and, over time, nephrocalcinosis (calcium deposits in kidney tissue), which can progress to chronic kidney disease; this is the same mechanism by which cholecalciferol kills rodents — kidney failure from calcium toxicity
- • Liver burden — vitamin D is a fat-soluble vitamin that must be processed by the liver; high-dose supplementation over years creates a sustained metabolic load; 25-OH vitamin D accumulates in fatty tissue and the liver itself
- • Paradoxical bone loss — a 2019 JAMA study found that high-dose vitamin D supplementation (above 4,000 IU) did not improve bone density and may have worsened it; this is the opposite of what most people supplementing for bone health expect; excessive vitamin D actually activates bone resorption at high levels
- • Vitamin A and K depletion — fat-soluble vitamins compete for absorption and regulatory pathways; chronic high-dose vitamin D supplementation can deplete fat-soluble vitamins A and K, creating downstream hormonal and metabolic disruption
- • Takes years to clear — fat-soluble vitamin D accumulates in fatty tissue and remains stored in the body long after stopping supplementation; toxicity symptoms may persist and the body's regulatory mechanisms take 1–3+ years to normalize after high-dose supplementation is discontinued
Whole Food Vitamin D Sources (the real thing)
When sunlight isn't available, the body's most bioavailable dietary sources of vitamin D come packaged with co-factors the isolated supplement lacks:
- • Wild-caught oily fish (sardines, mackerel, herring, sockeye salmon) — highest food-form vitamin D; comes with natural phospholipids and co-factors
- • Pasture-raised egg yolks — vitamin D content is dramatically higher than conventional eggs; the yolk matrix provides natural fat-soluble co-factors
- • Beef liver from grass-fed animals — concentrated vitamin D in its natural food matrix
- • Cod liver oil (traditional whole food form, not isolated fractions) — naturally contains vitamins A and D in their evolutionary ratio
- • UV-exposed mushrooms (gills up in midday sun for 30–60 minutes) — dramatically increases ergocalciferol (D2) content
Bottom line: sunlight is the source your body was designed to use. Whole foods are the dietary bridge when sunlight is insufficient. Isolated vitamin D supplements are not a neutral intervention — they carry real risk with long-term use.
Sunscreen: What You Were Not Told
The widespread recommendation to apply sunscreen daily — including on children, infants, and during everyday non-beach activity — is presented as purely protective. The ingredients in most commercial sunscreens tell a more complicated story.
Common Sunscreen Ingredients and Their Documented Concerns:
- • Oxybenzone (benzophenone-3) — endocrine disruptor; detected in blood within 30 minutes of application; found in human breast milk, urine, and amniotic fluid; FDA proposed in 2019 that oxybenzone cannot be classified as "generally recognized as safe and effective" (GRASE) due to systemic absorption; associated with hormone disruption in animals; listed as a coral reef toxin and banned in Hawaii for environmental harm
- • Octinoxate (octyl methoxycinnamate) — absorbed systemically; thyroid hormone disruption in animal studies; found in human blood and breast milk; also banned in Hawaii for coral reef toxicity
- • Homosalate — FDA flagged for systemic absorption exceeding safety thresholds; disrupts estrogen and androgen signaling in studies; absorbed at levels 16x the FDA's safety threshold in clinical testing
- • Avobenzone — degrades in sunlight to form potentially toxic photoproducts; may react with chlorinated water to form compounds with mutagenic properties
- • Nanoparticles (in some physical sunscreens) — nano-zinc and nano-titanium dioxide can penetrate damaged skin and mucous membranes; cellular toxicity concerns at the nano scale differ from bulk material safety
- • Parabens and preservatives — estrogenic activity documented; detected in breast cancer tumor tissue
- • Fragrance and "natural" additives — thousands of unlisted chemicals under the "fragrance" umbrella; many are sensitizers and endocrine disruptors
What the FDA Says (but doesn't say loudly)
In 2019 and 2021, the FDA proposed that only two sunscreen active ingredients qualify as GRASE (generally recognized as safe and effective): zinc oxide and titanium dioxide in non-nano form. Twelve chemical UV filters — including oxybenzone, octinoxate, homosalate, avobenzone, and others — were proposed as "insufficient evidence of safety." They remain on the market while that review drags on.
The research on whether sunscreen reduces melanoma mortality is surprisingly mixed. Non-melanoma skin cancers (basal cell and squamous cell) are largely benign and highly treatable. Melanoma correlates most strongly with indoor fluorescent light exposure and intermittent burning episodes — not cumulative total sun exposure. The countries with the highest melanoma rates (Australia, New Zealand) are also among the highest sunscreen-using populations.
What to use instead: Shade and clothing during the hottest midday hours. Broad-brimmed hats. Non-nano zinc oxide formulations for genuine high-UV situations (beach, snow, extended outdoor work). EWG's Skin Deep database (ewg.org/skindeep) rates sunscreen ingredients for safety — the contrast between what's on drugstore shelves and what EWG rates as acceptable is significant.
Studies, Videos & Resources
Supplement Risks Research
Benefits of Sunlight Research
Tools
Videos & Lectures
Note: This information is for educational purposes. Individual sun exposure guidance varies with skin type, latitude, and health history. Work with a qualified practitioner familiar with photobiology for personalized guidance.
Video Transcript
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Most people today have been told they're vitamin D deficient and handed a bottle of supplements. But here's what almost no one tells you: vitamin D in pill form is not the same as what your body makes from sunlight — and the sun does far more for you than make vitamin D.
The Supplement Problem
Cholecalciferol — the vitamin D3 in most supplements — was registered in 1984 as a rodenticide. Rat poison. At high doses, it causes fatal calcium overload in rodents. At the lower doses in supplements, the long-term cumulative effects haven't been adequately studied.
Research comparing sunlight to supplementation directly found that sun exposure improved cardiovascular markers significantly better than the pill. A 2019 JAMA study on high-dose vitamin D found no improvement in bone density — and potential harm at higher doses.
What the Sun Actually Does
Sunlight isn't just vitamin D. It lowers blood pressure by releasing nitric oxide from the skin. It lowers blood sugar. It improves cholesterol. It increases melatonin — your cancer-protective sleep hormone. It boosts immune function, sex hormones, and oxygen-carrying capacity of the blood. It directly improves mood and is associated with reduced suicide rates. It shapes your gut microbiome.
None of those effects come from a supplement.
The Danger of Avoidance
A Swedish study following 30,000 women for 20 years found that those who avoided the sun had a mortality rate 2 to 3 times higher than those with the highest sun exposure. The researchers noted that sun avoidance carries health risks comparable to smoking. We've been afraid of the wrong thing.
The Solar Callus Protocol
The key is building what's called a solar callus — conditioning your skin to the sun gradually, the way your feet adapt to walking barefoot.
Start with sunrise every morning — bare skin, bare eyes. The early morning light is low UV but sets your circadian clock. Use the DMinder app to track when to go out for vitamin D production. Expose skin without sunscreen during that window. If you start to turn pink, go into shade — don't burn. Eat vitamin C-rich whole foods before longer sessions — bell peppers, citrus, kiwi, papaya — to support your skin's antioxidant defenses. Food, not a supplement.
Over 6 weeks, your skin adapts. Your tolerance increases. Your body gets what it needs from the source it was designed to use.
Sunscreen
One more thing — sunscreen. What most people are applying every day contains oxybenzone, octinoxate, and homosalate — chemicals that absorb through the skin into the bloodstream within 30 minutes of application. The FDA in 2019 said there is insufficient evidence that these chemicals are safe. Only zinc oxide and titanium dioxide in non-nano form cleared their review. That information is also in the written article below.
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The sun is not your enemy. It's medicine. It always has been. We just forgot.
All research is in the Resources tab. This is The Undoctored.