Older women suffering from diabetes who supplement high doses of vitamin C may be increasing their risk of mortality.New research published in the November edition of the American Journal of Clinical Nutrition suggests that postmenopausal women with diabetes, who have a high intake of vitamin C, may have an increased risk of cardiovascular disease mortality. The researchers from the University of Minnesota in Minneapolis noted that although vitamin C acts as a potent antioxidant, it can also be a prooxidant and glycate protein under certain in vitro circumstances. “These observations led us to hypothesize that a high intake of vitamin C in diabetic persons might promote atherosclerosis,” said the scientists.