Myth-buster
A three-year trial of 2,000 IU/day vitamin D3 in 1,848 older adults found it did not budge a key bone-remodeling marker — but a simple home strength routine did.
This null result challenges any assumption that vitamin D alone meaningfully alters sclerostin, a protein that regulates bone formation, at this dose in healthy seniors — though the picture is far from settled, as this is one of the first studies to test the specific pairing head-to-head.
Sclerostin is a protein that normally slows down new bone formation; the study measured whether supplements or exercise could lower it. Over three years, neither vitamin D3 nor omega-3s alone made a dent in sclerostin levels, but a home-based strength exercise program — with or without omega-3s — did. The same study also found no effect on two other bone turnover markers, narrowing the scope of any potential benefit.
Where this fits in the evidence
This is among the first studies we've indexed on Vitamin D3 for Reduced Serum Sclerostin Level — treat it as an early signal until more research accumulates.
The study
- Randomized Controlled Trial (RCT)
- n = 1,848
- 2024-12-09
- The Journal of clinical endocrinology and metabolism
- PubMed: 39657964
- DOI: 10.1210/clinem/dgae859
- Full study breakdown →
This is a plain-language summary of a research finding, not medical advice. Pillser surfaces research signals to help you decide what's worth investigating — always consult a qualified professional before changing what you take.