Questions Remain After New 'Andro' Study Release
WebMD News Archive
Feb. 8, 2000 (Washington) -- Androstenedione, a supplement sold in health
food stores and taken by baseball great Mark McGwire, increased the amount of
testosterone in men who took it for a week. That's according to a new study in
the Journal of the American Medical Association, which was funded by
Major League Baseball and the Major League Baseball Players Association.
But that study is being criticized because the Harvard researchers did not
investigate whether "andro" helped the men pump up their muscles. And
some experts tell WebMD that not only is andro ineffective for this purpose, it
is harmful and should be withdrawn from the market.
"Nobody cares that it raised testosterone levels," Charles E.
Yesalis III, MPH, ScD, tells WebMD. "People who are buying this are not
buying it for increasing their testosterone level ... they are buying it to
increase their muscle mass and strength and enhance their physical appearance.
The big question still remains. Are these changes of a magnitude to do that? If
you asked me, does androstenedione work, I would say no."
Yesalis was not involved in this new study, but spoke out against andro last
year after another study was published showing that andro raised levels of
estrogen -- a female hormone -- in men who consumed it for eight weeks while
involved in weight-training activities. In that study, the supplement had no
effect on the men's muscle gain, compared to men who also trained and did not
take andro. The study also showed that andro caused a drop in the HDL
"good" cholesterol in these men.
This new study also showed increases in estrogen levels approaching those
found in women, a fact that should sound alarms that andro could be bad news,
especially for men and children, Yesalis says.
Andro, available without a prescription and not regulated by the FDA,
received widespread publicity after it was revealed that McGwire, the home-run
baseball record-holder, had used it. Although the substance is permitted in
baseball, it is banned by the National Football League, the National Collegiate
Athletic Association, and the International Olympic Committee.
The new Harvard study was undertaken by Benjamin Z. Leder, MD, Joel S.
Finkelstein, MD, and others at Harvard University and Massachusetts General
Hospital in Boston. In this study, 42 healthy men, 20-40 years old, were
selected to receive one of two doses of andro or a placebo. There is no
standard dose of andro. During the study period, the men's blood testosterone
concentrations rose by 34% in the men taking 300 mg per day. There was no
significant change in the testosterone level in the men taking 100 mg or a
placebo. Their levels of estrogen also were elevated beyond what is normal for
men, a situation that could potentially can cause feminizing effects in men,
including breast tissue enlargement.