Methylation is a vitamin-requiring biochemical process in the body that is critical for maintaining mental and physical health. Methylation helps convert the problematic amino acid metabolite homocysteine into the amino acids methionine and cysteine. Consistent recycling of homocysteine is vital for supporting cardiovascular health. Proper methylation can be inhibited by nutrient deficiencies, especially of folic acid, B6and B12. Certain medications such as acetaminophen, aspirin, ibuprofen and oral contraceptives can also deplete blood levels of these crucial B vitamins, reducing the body’s vital methylation capacity.
Adequate folate status is critical for maintaining optimal methylation, red blood cell balance, DNA and RNA synthesisand healthy cell division and replication. Folic acid is converted into its metabolically active form, 5-MTHF, by the enzyme methylenetetrahydrofolate reductase (5-MTHFR). 5-MTHF donates its methyl group to vitamin B12 (cobalamin), forming methylcobalamin. Methylcobalamin helps convert the problematic amino acid metabolite homocysteine into the amino acid methionine. 
Vitamin B12 (methylcobalamin) works along with folic acid in many body processes, including the synthesis of DNA, red blood cells and supporting health of the myelin sheath, the insulating exterior that surrounds nerve cells. B12 is found primarily in animal foods. Vegetarians and the elderly are at highest risk for B12 deficiency.  B12 is considered by many to be a vital nutrient required to balance homocysteine levels. Methylcobalamin is the biologically active form of B12 and supports up-regulation of methylation pathways. 
Vitamin B6 (pyridoxine) is a B vitamin that is required for more than 60 different enzymatic reactions that occur in the body. Vitamin B6 works along with folic acid and B12 for in the recycling of homocysteine. B6 also supports a healthy cardiovascular system by promoting healthy platelet aggregation and aids in maintaining healthy blood pressure.  Vitamin B6 is required for the activation of lysyl oxidase, an enzyme responsible for the cross-linking of collagen, and elastin, which is crucial for maintaining healthy circulation and arterial function. 
Trimethylglycine (Betaine) functions in the body as a unique methyl donor, supporting liver function and detoxification pathways and the conversion of homocysteine to methionine. [5,6]Trimethylglycine also works alongside B6, B12 and folic acid in maintaining normal homocysteine levels.
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