Method for lowering serum homocysteine

1. A method for lowering the amount of homocysteine in the blood of an individual comprising administering to the individual in need thereof an amount of a composition comprising a homocysteine lowering agent effective to lower the amount of homocysteine in the blood of the individual, wherein the agent is selected from the group consisting of:

a) dipeptides consisting of isoleucine, leucine, valine, or glycine, and combinations thereof;

b) tripeptides consisting of isoleucine, leucine, valine, or glycine, and combinations thereof;

c) alpha-ketobutyrate;

d) propionyl CoA; and

e) combinations of a) through d);

wherein the amount of homocysteine in the blood of the individual after administration of the agent is lower in comparison to the amount of homocysteine in the blood of the individual prior to administration of the agent.

2. The method of claim 1 , wherein the dipeptides or tripeptides of a) or b) comprise glycine and are administered in a dosage of from 0.5-5 grams per day.

3. The method of claim 1 , wherein the agent is an L-isoleucine dipeptide.

4. The method of claim 1 , wherein the agent is a dipeptide consisting of L-isoleucine and one of L-valine or L-leucine.

5. The method of claim 1 , wherein the agent is an L-isoleucine tripeptide.

6. The method of claim 1 , wherein the agent is a tripeptide consisting of at least one L-isoleucine and L-leucine or L-valine.

7. The method of claim 1 , wherein the agent is a tripeptide consisting of L-isoleucine, L-leucine and L-valine.

8. The method of claim 1 , wherein the composition is administered orally.

9. The method of claim 1 , wherein the agent is selected from alpha-ketobutyrate and propionyl CoA.