Q. I've heard that B-vitamin supplements can help prevent heart disease. Do you recommend them?
A. No. I do not know of any benefit of taking B vitamins to prevent heart disease. Folic acid had a lot of promise but studies so far have not shown a benefit. [Dr. Ades notes that niacin, a B vitamin, can help some individuals lower blood cholesterol but it should only be taken under a doctor’s guidance, as it can have side effects.