TMG is also called glycine betaine, but the name "trimethylglycine" signifies that it has three methyl groups attached to each molecule of glycine. Betaine was discovered to be beneficial to heart health back in the 1950's. Research showing TMG's ability to promote healthy levels of homocysteine alone or in conjunction with other nutrients, confirms its status as an important nutrient for cardiovascular health. When a TMG methyl group is donated to a molecule of homocysteine, it is converted first to the nontoxic amino acid, methionine, then to S-adenosyl-methionine