Elevated plasma homocyst(e)ine is a risk factor for vascular disease in middle-aged men. Supplementation with folate, and to some extent vitamins B12 and B6, can reduce plasma homocyst(e)ine levels. There is also evidence from in vitro studies that the adverse atherogenic or thrombotic effects of Lp(a) may be greatly enhanced by homocyst(e)ine. The high prevalence of low levels of folate and vitamins B12 and B6 among the elderly in the United States has led to the hypothesis that a substantial portion of cardiovascular morbidity and mortality among older persons could be prevented by increasing intake of these nutrients to reduce plasma levels of homocysteine. Little is known, however, regarding the relationship of homocysteine, folate, B vitamins, and Lp(a) to cardiovascular disease among the elderly, among whom CVD represents the leading cause of morbidity and mortality.