Evidence-based articles about vitamin D, sun exposure, and health optimization.
77 articles
Food alone rarely closes the vitamin D gap — and how much sun helps depends entirely on where you live. Here's what the evidence shows by latitude, season, and diet.
People with darker skin tones are 3–5 times more likely to be vitamin D deficient — not because of sun avoidance alone, but because melanin biology changes everything. Here's what the evidence shows.
Food provides a fraction of the vitamin D most adults need. Here's what the evidence shows about dietary ceilings, sun synthesis, and when supplements fill the gap.
Most vitamin D-rich foods deliver far less than a single sun session. Here's what the evidence says about dietary ceilings, food sources, and when diet simply isn't enough.
Low vitamin D appears repeatedly alongside hormonal imbalances — but the relationship with estrogen is more specific than most articles admit. Here's what the evidence actually shows.
Standing desks near windows feel healthier, but glass blocks UVB almost entirely. Here's what the evidence says about indoor light, vitamin D synthesis, and what actually works.
Athletes consistently test lower for vitamin D than non-athletes in controlled studies. Here's what randomized trials show about levels, muscle recovery, and injury risk.
Most adults get far less vitamin D from food than they assume. Here's what the evidence shows about dietary sources, sunlight synthesis, and how to close the gap.
Fatigue, bone pain, and low mood are often traced to low vitamin D — but the evidence linking specific symptoms to 25(OH)D thresholds is more precise than most people realize.
Estrogen decline during menopause accelerates vitamin D insufficiency and bone loss. Here's what clinical trials and cohort data show about needs, testing, and dosing in this life stage.