Some products aren’t what they seem.

A study published in the JAMA Network Journal suggests that an alarmingly high percentage of bodybuilding products sold online are mislabeled and contain unapproved drugs.

Researchers tested 44 products they bought online that were marketed as nonsteroidal selective androgen receptor modulators (SARMs), which mimic the effect of testosterone and help build muscle.

Several companies are developing SARMs as potential treatment for conditions such as muscle-wasting disorders, but the The U.S. Food and Drug Administration hasn’t approved any SARMs for medical treatment yet.

Overall, only about half of the products actually contained SARMs, one in four products contained ingredients that weren’t on the label, and 59 percent had more or less than the advertised amounts of certain ingredients.

Co-author Dr. Shalender Bhasin of Harvard Medical School Brigham and Women’s Hospital in Boston wrote:

“Our findings show that people should be extremely careful about using these unapproved drugs purchased over the internet not only because these drugs can have harmful effects on their health, but also because the labels cannot be trusted and many products may contain other chemicals not listed on the label whose safety is unknown.”

Some products were found to contain a drug that increases growth hormone. Four products were found to contain the breast cancer drug tamoxifen.

Some of the undiscolsed compounds – Ostarine, Andarine, LGD-4033 and ibutamoren – have been tested in humans but lack FDA approval.

Development of another compound found in the products, GW-501516, was halted because of safety concerns.

Another, SR9009, has been through some preliminary clinical trials but hasn’t yet been tested in humans.

“But people do spend millions of dollars on unregulated drugs every day – and at their peril,” said Dr. Richard Auchus, author of the accompanying editorial and a researcher at the University of Michigan in Ann Arbor.

Auchus says that Vitamin D and calcium are the only supplements people should buy, and even then consumers should only shop from legitimate suppliers like the website for a drugstore chain.

Interestingly the editorial does not mention the illegality of anabolics as a potential cause for the prevalence of dangerous mislabeled supplements.

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