The non-essential amino acid homocysteine is produced in the body with the metabolism of the amino acid methionine.
Homocysteine is usually broken down into the amino acid cysteine. Cysteine is one of the amino acids needed by the cells to make intracellular glutathione. If your body does not convert homocysteine to cysteine the intracellular glutathione conversion will not take place.
The rapid conversion of homocysteine is critical. If conversion takes place too slow, homocysteine will accumulate in the body and damage cell membranes, damage blood vessels, increase the risk of cardiovascular disease, and atherosclerosis.
Rapid conversion of homocysteine requires an individual to have adequate amount of vitamin B6, B12, and folate. Over 50% of the population in the world has a genetic defect in the pathway needed to metabolize B6, B12, and folate.