Homocysteine PF (Protection Factors) contains methyl group (CH3) donors from Methyl B12, TMG and Folic Acid, plus vitamin B6 for additional reduction of homocysteine. Methyl groups convert homocysteine, a toxic amino acid, into methionine, which is an essential amino acid. Methylation is inhibited by poor diet (excessive protein and fat intake or inadequate nutrition), alcohol, caffeine, smoking and genetic predisposition. Impaired methylation elevates homocysteine levels. Methylcobalamin (Methyl B12) is better absorbed, retained and utilized than cyanocobalamin, the typical form of vitamin B12. Methylfolate transfers a methyl group to cobalamin to form Methylcobalamin via the enzyme methionine synthetase. Therefore, Methyl B12 is the most active and most important form of B12.