SAMe (known as S-adenosylmethionine) is not an herb or a hormone. It’s a molecule that all living cells, including our own, produce constantly. To understand SAMe you first need to understand methylation and the importance of this process. Methylation is a simple transaction in which one molecule donates a methyl group (four-atom appendage) to a neighboring molecule within our body. SAMe’s methyl group is composed of one carbon and three hydrogen atoms. These transactions have far-reaching effects that affect everything from fetal development to brain function. It regulates the expression of genes, preserves fatty membranes that insulate our cells, and helps regulate various hormones including serotonin, melatonin, dopamine, and adrenaline. Without SAMe there would be no methylation.