If you’re talking vitamin D and expecting it to lower your risk of getting type 2 diabetes when you get older, it’s time to lower your expectations.
A new study, the largest of its kind, has found that taking 4000 international units (IU) per day, which is on the upper limit of the recommended intake, may double the amount of vitamin D in the blood but it gives most people roughly the same chance of developing blood sugar problems as people who don’t take the vitamin.
After about 2.5 years, diabetes appeared at a rate of 9.4% per year with vitamin D supplements and 10.7% with placebo capsules, an insignificant difference. All the patients were already at high risk for developing type 2 diabetes and 80% already had adequate levels of the vitamin.
Vitamin D also keeps bones healthy and doctors may recommend a supplement for other reasons as well. Many foods add the vitamin.