Scientists from Manchester and Kyoto universities warned this week that the popular dietary supplement SAMe (S-adenosylmethionine) could be toxic to humans, and should be avoided “until proven safe”.
SAMem is marketed as a dietary supplement in the UK (where it is widely available online), the US and Canada, and is available as a prescription medicine in parts of Europe and Asia. It is used to manage a range of conditions including low mood, joint pain and liver disorders.
The Manchester and Kyoto teams discovered a toxicity problem with SAMe unexpectedly during a study of mice. The teams were studying how the biological clock in mice is influenced by different compounds. With SAMe, they were attempting to promote SAMe-related metabolism of the animals, and were surprised to find an opposite inhibitive effect.
SAMe-related metabolism is very ancient, and critical for the biological clock in human and plant cells, worms, fruits flies and even bacteria.
Manchester University’s Dr Jean Michel Fustin said: “This worrying effect of SAMe on the body clock in mice strongly suggested it will be toxic in human as well, which we actually confirmed in human cells.
“This worrying effect of SAMe on the body clock in mice strongly suggested it will be toxic in human as well, which we actually confirmed in human cells”
“The health benefits that manufacturers claim are questionable to say the very least. And because it’s unclear what dose is safe, there is a good chance that a safe dose will be exceeded – if one exists at all.
“We should trust the amount of SAM our own body produces, unless there are clear clinical signs of deficiencies.”
Adenine and methylthioadenosine inhibit chemical reactions called methylations that occurs in every cell and tissue in the body. SAMe is required for these reactions, and it was expected that more SAMe would promote methylations. But the opposite turned out to be the case in the study.
The researchers note that disruptions to
Natural health specialists would almost certainly challenge the researchers’ negative comments about SAMe’s benefits. US website Web MD says SAMe has similar effectiveness to Ibuprofen for reducing symptoms of osteoarthritis and that oral supplementation with SAMe is “as effective as the prescription drug ursodeoxycholic acid” in treating reduced or blooded flow of bile from the liver.
Image: What manufactures say, and what the research teams say about SAMe. Manchester University