Amazon.com: Allergy Research Group Homocysteine Plus Supplement with Setria Glutathione, Vitamin B Complex, Trimethylglycine, Vegetarian Capsules 90 Count : Health & Household Homocysteine is an amino acid. Vitamins B12, B6 and folate break down homocysteine to create other chemicals your body needs. High homocysteine levels may mean you have a vitamin deficiency. With a Folic Acid, Homocysteine & Methylation The Facts High homocysteine doesn't usually cause symptoms on its own, but it can signal vitamin deficiencies or other health issues and it's something you can check with a simple blood test Impaired Homocysteine Metabolism and Atherothrombotic Disease Laboratory Investigation