Aneth David, Ph.D.

This is how health misinformation works: start with a true association, then smuggle in a false conclusion. Yes — low vitamin D levels are associated with frequent illness, depression, fatigue, and poor metabolic health. That part is uncontroversial. What Gary Brecka leaves out is the inconvenient word association. What the evidence actually says Low vitamin D is largely a marker, not a magic lever: •People who are older, chronically ill, obese, depressed, sedentary, or inflamed tend to have lower vitamin D. •Raise the vitamin D level, and in randomized trials… most outcomes don’t improve. •No consistent reduction in infections •No meaningful antidepressant effect •No metabolic rescue •No vitality upgrade If vitamin D were the causal driver Brecka implies, supplementation trials would show dramatic benefits. They don’t. The sunlight sleight of hand “15–30 minutes of sunlight” sounds primal and wise — but: •It depends on latitude, season, skin tone, age, clothing, and sunscreen •Winter sun above ~37° latitude produces near-zero vitamin D •Sun exposure raises vitamin D modestly — it does not cure depression, fatigue, or metabolic disease Bottom line •Vitamin D deficiency should be corrected — absolutely •Vitamin D is not a treatment for modern disease •Low vitamin D is usually a symptom of poor health, not its cause This is classic influencer alchemy: Confuse correlation for causation, add sunlight, sell certainty. Medicine is harder than that — which is why slogans outperform evidence on social media.