Surprising
Vitamin D cut diabetes risk 19% — but only in people with a specific genetic variant, a 2,098-person RCT found
This is the first solid evidence that vitamin D's effect on diabetes prevention may depend on your DNA, but it's a single trial finding that needs replication before you should act on it.
In a randomized trial of 2,098 adults with prediabetes, taking 4,000 IU of vitamin D3 daily reduced the risk of developing diabetes by 19% — but only among the 1,480 participants who carried certain variants (AC or CC) of the ApaI gene. Those with the AA genotype saw no benefit at all, suggesting that genetic testing might one day help decide who should take vitamin D for diabetes prevention.
Where this fits in the evidence
This is among the first studies we've indexed on Vitamin D for Reduced Risk of Diabetes — treat it as an early signal until more research accumulates.
The study
- Randomized Controlled Trial (RCT)
- n = 2,098
- 2026-04-23
- JAMA network open
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.