According to a finding being presented at the American Society of Nephrology’s 42nd Annual Meeting and Scientific Exposition in San Diego, CA, athletes and bodybuilders making use of anabolic steroids to gain muscle mass and strength may destroy their kidney function in the process.

From Sciencedaily.com:

When the bodybuilders discontinued steroid use their kidney abnormalities improved, with the exception of one individual with advanced kidney disease who developed end-stage kidney failure and required dialysis. Also, one of the bodybuilders started taking steroids again and suffered a relapse of severe kidney dysfunction.

The researchers propose that extreme increases in muscle mass require the kidneys to increase their filtration rate, placing harmful levels of stress on these organs. It’s also likely that steroids have direct toxic effects on the kidneys. “Athletes who use anabolic steroids and the doctors caring for them need to be aware of the potentially serious risks to the kidney,” said Dr. Herlitz.

Leal Herlitz, MD (Columbia University Medical Center) and her colleagues said that athletes and bodybuilders on steroids in the long run can witness development of protein leakage into the urine and severe reductions in kidney function.

The involved researchers proposed that extreme increases in muscle mass require the kidneys to increase infiltration rate to place harmful stress levels on these organs.