The present invention provides a method for reducing the amount of homocysteine in the blood of an individual. The method comprises administering to the individual a composition comprising a homocysteine lowering agent in an amount effective to lower the amount of homocysteine in the blood of the individual. The homocysteine lowering agent is selected from A dipeptides consisting of isoleucine, leucine, valine, or glycine and combinations thereof; tripeptides consisting of isoleucine, leucine, valine, or glycine and combinations thereof; alpha-ketobutyrate; propionyl A CoA, and combinations thereof.