Man making anabolic steroid injection

(© Adamov -

COPENHAGEN, Denmark — “Juicing” may give gym rats and athletes a competitive edge over others, but experts warn it can also take a terrifying toll on a man’s body. Men who abuse steroids can be left with poor testicular function for years afterward, a recent study reveals.

Anabolic steroids are synthetic forms of testosterone and their abuse is prevalent among bodybuilders and athletes worldwide. Former U.S. double sprint champion Tyson Gay was banned for anabolic steroid doping.

People use steroids without a prescription to improve their athletic performance or get a more muscular look. Known side effects in men include breast growth, hair loss, shrunken testicles, and lower testosterone levels. Also called hypogonadism, low testosterone can cause lower sex drive, poor erections, and a low sperm count.

Researchers at Rigshospitalet, the largest hospital in Denmark, identified a hormone made by Leydig cells in the testicles that produce testosterone. These cells are a promising marker of how well the testicles are working. Because blood levels of testosterone can vary during the day, researchers are investigating a more stable marker than testosterone, called serum insulin-like factor 3 (INSL3).

The team included 132 participants from another study of men who did recreational strength training. Their ages ranged from 18 to 50 and averaged 32. They were split into three groups of men currently using anabolic steroids, men who used to use them, and those who had never used them.

Results show that among current steroid users, INSL3 was notably suppressed when compared with former users and never-users. Men who previously used steroid showed lower INSL3 concentrations, and the longer the use, the lower their INSL3 levels.

“Our results suggest a long-lasting impaired gonadal capacity in previous anabolic steroid users,” says Dr. Jon J. Rasmussen, the study’s principal investigator and a scientist at the hospital, in a statement.

Although the clinically relevant difference in INSL3 levels is not yet known, the findings indicate that prior steroid users may have an increased risk of low testosterone later in life, causing potential lower sex drive, poor erections, and low sperm count.

“The results raise the question whether some previous anabolic steroid users should receive medical stimulation therapy to increase Leydig cell capacity in the testicles,” says Dr. Rasmussen. “This therapy would include drugs used to block estrogen production or its conversion to testosterone, such as aromatase inhibitors and selective estrogen receptor modulators.”

The study, supported by Anti Doping Denmark, was published in the Journal of Clinical Endocrinology & Metabolism.

SWNS writer Laura Sharman contributed to this report.

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