High doses of B vitamins pose risks in patients with diabetes. B vitamins are recommended for lowering homocysteine, a risk factor for vascular disease and diabetic nephropathy. However, Canadian researchers found that patients with diabetes who took a daily supplement containing high doses of folic acid (2.5 mg), vitamin B6 (25 mg), and vitamin B12 (1 mg) for three year shad poorer kidney function, twice as many heart attacks, and six times as many strokes as patients taking placebo. "Given the recent large-scale clinical trials showing no treatment benefit, and our trial demonstrating harm, it would be prudent to discourage the use of high-dose B vitamins as a homocysteine lowering strategy," conclude the authors in the April 28 issue of JAMA.