Feb. 8, 2000 (Atlanta) -- Androstenedione, the popular supplement called 'andro,' might increase blood levels of the male hormone testosterone, but that does not mean taking it will lead to bigger muscles, experts say. And it could mean the development of potentially serious side effects down the road.
"For one thing, I do not think it should be classified as a dietary supplement," says Gary Wadler, MD, associate professor of clinical medicine at the New York University School of Medicine and an advisor to the U.S. government's 'drug czar.' "At the very least, it should be classified as a prescription drug ... Simply put, you're ingesting a supplement that your body is converting into a controlled substance."
Putting federal drug laws aside, Wadler says there's also a good health reason to avoid andro: the possibility of long-term adverse effects. "Clearly, we know from a variety of experiences with humans, that the effects [of hormones] may not be manifest for months, years, decades later." Wadler says an example of this phenomenon is the potential increased risk of cancer, many years later, in women who used the female hormones estrogen and progesterone.
"You have to remember that testosterone is metabolized ... to estrogen," Wadler says. It's the reason bodybuilders using drugs similar to androstenedione -- anabolic steroids -- sometimes develop large breasts and shrunken testicles. "People taking anabolic steroids have long known that is something they have to deal with," he says. "It was the price they had to pay for increased strength." The question is whether they'll pay a much higher price in years ahead.
And still open for debate is whether taking andro will even result in increased strength. Bodybuilding dogma says more male hormone means a greater potential for bigger muscles. But an endocrinology expert says that when it comes to andro, that's not necessarily so. "The amount of testosterone [produced] is not as important as the amount that can bind to particular tissues," says William Kraemer, PhD, professor and director of the Human Performance Laboratory at Ball State University in Muncie, Ind.
Testosterone binds to all sorts of tissues, Kraemer explains, so there's a real question whether muscle tissue benefits in particular from higher blood levels of the hormone. "If [androstenedione builds muscles], nobody's proven it yet," he says. "We're in the early stages of understanding it scientifically."