Tag
Vitamin D
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Vitamin D: uses, evidence, dosing and safety
Vitamin D is the most-studied supplement there is, and the pattern across thirteen uses is almost always the same: correcting a deficiency helps, and adding more on top of enough does not.
Aug 6, 2026
Vitamin K status did not protect bone in a VITAL analysis
Vitamin K is sold as the partner vitamin D needs for bones. In 771 participants of the VITAL trial, higher vitamin K status did not slow two-year bone loss or improve what vitamin D did.
Aug 6, 2026
Vitamin A, not D, tracked with better lungs in asthma
A Thorax study of 1,165 children and 1,041 adults with asthma found blood vitamin A levels tracked with better lung function, while vitamin D did nothing measurable in children.
Jul 26, 2026
US supplement use hit 60% as multivitamins fell and ashwagandha rose, across 25 years of data
A JAMA Network Open analysis of 63,442 adults across 25 years of national survey data found supplement use rose from 51% to 60%, with multivitamins falling and ashwagandha, collagen and elderberry rising.
Jul 25, 2026