2 ms·

I think this mostly has been debunked in the last 15 years, except in the unscientific health influencer space https://pubmed.ncbi.nlm.nih.gov/39017376/ https:

• agensaequivocum 1y ago
  Really the conclusion of that paper, that people are not vitamin D deficient, ought to be that people are sunlight deficient. This is why studies that involve supplementation of vitamin D frequently show no effect. Vitamin D is only one of many many ways in which light affects biology. The paragraph near the end about babies needing fortified milk because breast milk is insufficient in vitamin D is laughable. It seems pretty obvious that babies are one of the most, if not the most, sunlight deficient demographics.