( CNN) Selective androgen receptor modulators, known as SARMs, are pharmaceutical medications that imitation the effects of testosterone. Not yet approved by the US Food and Drug Administration, these compounds are often marketed to bodybuilders online as “legal steroids” that can help them look leaner and more muscular.
Most of the products sold online as SARMs contain either these unapproved substances alone — sometimes in quantities different from what is specified on the label — or other unapproved hormones and steroids, according to a study
published Tuesday in the medical publication JAMA.
“There are serious potential side effects, and there’s this wide-held misperception that these compounds are safe, ” said Dr. Shalender Bhasin, co-author of the new study and director of the research program in men’s health at Brigham and Women’s Hospital.