S-adenosyl methionine is a chemical compound essential in cellular growth and regeneration. It is also known as SAM and SAMe. This compound is created by a reaction of adenosine triphosphate (ATP) and methionine. It uses the metabolic pathways of transmethylation, transsulfuration, and aminopropylation within cells to carry out its function.
SAM has methyl group attached to it, which makes it chemically reactive. This allows it to operate in transmethylation reactions, as it can be donated to an acceptor substrate. Numerous nucleic acids, proteins, and lipids also benefit from the donation of the methyl group from s-adenosyl methionine. The actions SAM participates in are present throughout the human body, but the highest volume of SAM, both produced and used, is found in the liver. It is not necessary for humans to consume foods containing s-adenosyl methionine, since it is produced naturally.
This compound is sold as a supplement in the United States, typically under the name Sam-e, which is pronounced as sam-ee. It is also sold as a prescription drug in Russia and Italy, under brand names such as Gumbaral® and Samyr®. Research has been conducted into the effectiveness of SAM in combating depression, liver disease, and osteoarthritis. Multiple trials have shown that the supplement is beneficial in the treatment of depression and osteoarthritis. A 2003 study concluded that s-adenosyl methionine supplements were effective in managing knee pain due to osteoarthritis.
In the United States, this supplement has seen increasing popularity. The Dietary Supplement Health and Education Act (DSHEA), which was passed in 1994, allowed for the distribution of numerous substances, including s-adenosyl methionine, as supplements rather than drugs. By classifying such compounds as supplements rather than drugs, many companies were able to avoid the strict regulations that the United States Food and Drug Administration (FDA) places on drug production.
Low levels of SAM in the body were once thought to be a significant factor in the development of Alzheimer's disease. Later research determined that low levels of vitamin B12 were the more likely culprit. SAM levels are significantly lower in Alzheimer's sufferers, however, and recent clinical trials have shown that supplements of s-adenosyl methionine were able to limit cognitive impairment in mice displaying Alzheimer's-like symptoms.
This supplement should be consumed on an empty stomach. Foil packaging and storage in a cool, dry place can help to ensure the supplement does not degrade. Possible side effects of SAM use include insomnia, atherosclerosis, and an increased risk of heart attack. In rare cases, and in combination with other medications, SAM can cause what is known as serotonin storm, which is an overproduction of the neurotransmitter serotonin. At least one case of this condition has proven fatal.