Although studies have linked vitamin D deficiency to an increased risk of cardiovascular disease (CVD), evidence regarding whether vitamin D intake from foods or supplements is prospectively associated with lower CVD risk in healthy humans is limited and inconclusive.

The objective was to comprehensively evaluate the associations between both dietary and supplemental vitamin D and CVD risk.

In the Nurses' Health Study (1984-2006) and the Health Professionals Follow-Up Study (1986-2006)-consisting of 74,272 women and 44,592 men, respectively, who were free of CVD and cancer at baseline-we prospectively examined the association between vitamin D intake and incident CVD.

Over a total of 2,280,324 person-years of follow-up, we identified 9886 incident cases of coronary heart disease and stroke. After multivariate adjustment for age and other CVD risk factors, a higher total vitamin D intake (from foods and supplements) was associated with a decreased risk of CVD in men but not in women; the relative risks (95% CIs) for a comparison of participants who met the Dietary Reference Intake of vitamin D (≥600 IU/d) with participants whose vitamin D intake was <100 IU/d were 0.84 (0.72, 0.97; P for trend = 0.009) for men and 1.02 (0.89, 1.17; P for trend = 0.12) for women.

These observations suggest that a higher intake of vitamin D is associated with a lower risk of CVD in men but not in women. Further research is needed to confirm these findings and to elucidate a biological basis for potential sex differences.