Longevity & AgingYour Genes May Determine If Vitamin D Can Cut Your Diabetes Risk
A new analysis of the D2d randomized trial found that high-dose vitamin D3 supplementation (4,000 IU/day) significantly reduced the risk of progressing from prediabetes to type 2 diabetes — but only in people carrying specific vitamin D receptor gene variants. Among 2,098 adults with prediabetes, those with ApaI AC or CC genotypes saw a 19% lower risk of developing diabetes over 2.5 years. People with the AA genotype, about 30% of participants, showed no benefit. When combined with achieving blood vitamin D levels of 40–50 ng/mL or higher, risk reductions climbed dramatically — up to 83%. The findings suggest that genetic testing could help identify who actually benefits from vitamin D supplementation for diabetes prevention.
