Fitness and Weight Loss These bodybuilding supplements known as "Legal Steroids" are putting your health at risk

Selective androgen receptor modulators, known as SARMs, are drugs that are said to boost your athletic performance and make you look more muscular by mimicking the effects of testosterone without the negative side effects of using steroids, like damaging your liver or shrinking your balls.

But according to a new study published in JAMA, many products containing SARMs you can find online contain unapproved substances, hormones, and steroids. What’s more, most of the labels slapped onto these supplements are completely misleading.

For the study, the researchers analyzed 44 drugs marketed and sold as SARMS using procedures approved by the World Anti-Doping Agency for detecting banned substances in athletes. They found that 39 percent of the supplements tested contained unapproved drugs, like banned growth hormones or steroids, while 25 percent contained similar substances not even included on the label. In 59 percent of the products, the amount of compounds listed on the label was significantly different than what the analysis actually found.

“The compounds found in our analyses have not been approved by the FDA. Therefore, the pharmaceutical companies which were or are developing these compounds cannot sell these products and a physician cannot prescribe these drugs to patients,” explains study co-author Shalender Bhasin, M.B., B.S., professor of medicine at Harvard Medical School and director of the research program in men's health at Brigham and Women's Hospital. “Also, because these compounds are not approved by the FDA, there is very little information about their safety and efficacy. Some of the compounds have never been studied in humans.”

In October, the FDA released a warning statement about products that contain SARMs.

“Life threatening reactions, including liver toxicity, have occurred in people taking products containing SARMs,” the statement notes. “SARMs also have the potential to increase the risk of heart attack and stroke, and the long-term effects on the body are unknown.”

SARMs may actually produce side effects like steroids, says Dr. Bhasin. In addition to the risks above, the side effects of steroids include infertility and mental health problems like depression, aggression, or thoughts of suicide.

It’s not just elite athletes or bodybuilders looking into these supplements, says Dr. Bhasin, but rather younger guys who want to change the way they look. While the numbers aren’t concrete for SARMs just yet, 1 in 15 men worldwide have tried steroids at some point in their lives, according to an analysis of 271 studies published in the Annals of Epidemiology. The number for athletes and weightlifters is roughly three times higher.

So naturally, an alternative version of a muscle-boosting drug is appealing to some men. This, in turn, is contributing to the rise of body image disorders, like muscle dysmorphia, in young guys who aren’t athletes, says Dr. Bhasin.

While the study authors admit their findings should not represent all products containing SARMs, they do emphasize that more regulation is needed.

“The consumers may think that just because some of these compounds are being sold as 'nutritional supplements,' they must be safe,” says Dr. Bhasin. “This is not the case. These compounds do not meet the definition of nutritional supplements, and their safety has not been demonstrated.”