Vitamins as homocysteine-lowering agents.

Moderate hyperhomocysteinemia is, today, considered an established risk factor for cardiovascular disease. A graded dose-response relationship between plasma homocysteine concentration over its full range and cardiovascular risk strongly supports causality. Therefore, intervention studies with homocysteine-lowering vitamins are needed. This mini review shows that supplementation with folic acid not only markedly reduces elevated plasma homocysteine concentrations but also reduces normal homocysteine concentrations. Folic acid doses of < 1 mg/d may be effective. Supplementation with a combination of folic acid and cyanocobalamin will secure full homocysteine-lowering effect and prevent occurrence of vitamin B-12 deficiency during the course of therapy.