Yiqing Song, MD, ScD, from Brigham and Women’s Hospital in Boston, and colleagues identified and performed a meta-analysis of 21 prospective studies examining the association between blood levels of 25-hydroxyvitamin D (25[OH]D) and risk of incident type 2 diabetes, involving 76,220 participants and 4,996 incident type 2 diabetes cases.
The researchers found that higher levels of 25(OH)D were associated with a lower risk of type 2 diabetes (relative risk, 0.62 comparing the highest and lowest categories). The risk fell by 4% for each 10nmol/L increment in 25(OH)D levels. The association persisted regardless of sex, length of follow-up, study sample size, diabetes diagnostic criteria, or 25(OH)D assay method.
“Our meta-analysis showed an inverse and significant association between circulating 25(OH)D levels and risk of type 2 diabetes across a broad range of blood 25(OH)D levels in diverse populations,” Song and colleagues conclude.