Association between higher blood level of vitamin D and lower risk of diabetes among women is reported

An observational study in the Nurses’ Health Study – a longitudinal cohort of women – supports an association between higher blood level of vitamin D and lower risk of developing diabetes. After adjusting for many factors known to influence diabetes risk – including obesity – our team reported that higher blood level of 25-hydroxyvitamin D was associated with a lower risk of future diabetes among women free of diabetes at baseline. Specifically, women in the top quartile of blood 25-hydroxyvitamin D level (mean level of 33 ng/mL) had a 48% lower risk of developing diabetes compared to women in the bottom quartile (mean level of 14 ng/mL). The benefit was larger among overweight/obese vs. normal weight women. Because of the observational nature of the study, we cautioned that a causal association between vitamin D and diabetes risk needs to be needs to be confirmed in a properly designed and conducted clinical trial.

The study was funded by the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) of the National Institutes of Health (NIH).

Results were published in Diabetes Care.