Homocysteine, B12 and the Cardiovascular Risk Marker You've Never Been Offered
Homocysteine sits at the crossroads of one-carbon metabolism. It is normally recycled either to methionine (requiring B12 and folate) or transsulfurated to cysteine (requiring B6). Failure of these pathways — whether nutritional, genetic (MTHFR polymorphism) or renal — allows homocysteine to accumulate.