After 20 years of follow-up, it was concluded that a combined daily intake of over 1,200 mg of calcium and more than 800 IU of vitamin D was associated with a 33 percent lower risk of type-2 diabetes. Interestingly, dietary vitamin D intake did not appear to provide any statistically significant benefit. But the women who supplemented with at least 400 IU of vitamin D had a 13% lower risk of diabetes when compared to those who took less than 100 IU per day. Both dietary and supplemental calcium resulted in decreased risk of type-2 diabetes, and those with overall intakes above 1,200 mg had a 21% lower risk than those who got less than 600 mg per day. Elevated intakes of calcium and vitamin D, especially from supplements, are significantly associated with lower incidence of type-2 diabetes.
My recommendation: Active Calcium
