Muscle Supplements

Claims, Benefits: Improves athletic performance.

Bottom Line: Made famous by Mark McGwire, andro is taken by many body builders and athletes. Since it can be converted by the body into sex hormones, it's considered an anabolic steroid. Andro and many similar supplements were banned in January 2005 because of the many potential adverse effects. But new products are quickly taking their place, and causing new worries.

Full article, Wellness Letter, April 2005:

Muscle in a bottle?

A federal law banning over-the-counter sales of the dietary supplement androstenedione (commonly called andro) and 25 related compounds went into effect in January. Like anabolic steroids, these are now controlled substances. A so-called muscle builder, sports fuel, and sex-drive enhancer, andro was best known for its use by Mark McGwire during his 70-home-run 1998 season. Classified as steroid precursors or pro-hormones, andro and its siblings can be converted to testosterone (and/or other hormones) in the body. By boosting testosterone they’re supposed to build muscle and enhance athletic and sexual performance, though there is much debate about how effective they really are.

By affecting hormones, these substances could have serious long-term adverse effects, including blood-clotting disorders, increased aggression, reduced HDL (“good”) cholesterol, and liver problems. In men, they can also cause breast enlargement, testicle shrinkage, increased body hair, and accelerated growth of prostate cancer. In women, they could cause male pattern baldness, excessive facial hair, deepened voice, and possibly abnormal menstruation and increased risk of breast and endometrial cancer.

Yet millions of Americans, from professional athletes to week-end exercisers and kids, have used andro in one form or another, often combined with other risky prohormone ingredients.

Sidestepping the ban

The ban is good news. It covers many andro siblings and look-alikes. But marketers are simply wiggling around the law and producing new “muscle-building” supplements. Many have replaced andro with a cocktail of other ingredients—which may not be much safer.

Among the newer ingredients are Tribulus terrestris, Eurycoma longifolia, and other herbs touted as hormone boosters. Despite the claims, there’s no scientific evidence they build muscle or do anything to enhance performance. As to their safety, Dr. Gary Wadler, associate professor of clinical medicine at New York University, told the Wellness Letter that his concern was not whether tribulus builds biceps, but that the herb has been linked to “staggers” in sheep, a disease causing paralysis and weakness, as well as other disorders. Darin Van Gammeren, an exercise physiologist at the University of Florida, adds that tribulus has no known benefits for athletes, and that no toxicity studies have ever been done in humans. But several studies have shown it to be harmful in animals.

Dr. Wadler points out the analogy between andro and ephedra—a dangerous weight-loss product that the FDA finally banned, only to see supplements immediately appear with ingredients very similar to ephedra. There’s always another substance that can be substituted under a different name, until it too starts to attract adverse attention.

All you need to know

Herbs, drugs, and potions that claim to make you hit home runs, bulk up like Mr. America, and turn into a tiger in bed are too numerous to count. Now that the government has cracked down on one class of them, manufacturers have quickly begun to sell others. The simplest way to protect yourself is not to believe the self-serving claims. Don’t take any supplement that promises to enhance athletic performance, build muscle, or improve your sex drive. Experimenting with hormones, or anything that may affect them, is always risky. In particular, don’t take anything with tribulus in it. If you are counseling kids who want to excel in sports, persuade them to do it through training, not pills.

UC Berkeley Wellness Letter, April 2005