ST. LOUIS -- Cardinals first baseman Mark McGwire, concerned over his impact on children and teen-agers, says he has stopped using androstenedione, a controversial diet supplement.
National sales of the substance have soared since last summer when McGwire acknowledged using it to enhance workouts during his record-70-homer season.
This prompted medical experts to warn of possible serious health consequences for young athletes who emulate McGwire by taking andro.
McGwire said he decided it was best to disassociate himself from the supplement and that he eliminated androstenedione from his routine at the start of this baseball season.
"I thought long and hard about it, and I don't like the way it was portrayed, like I was the endorser of the product, which I wasn't," said McGwire, who was one home run away from his 500th career homer before Thursday's game against the San Diego Padres at Busch Stadium.
"I don't like how it's portrayed that young kids take it because of me. I always discouraged children from taking it."
McGwire said he hadn't said anything about giving up andro because he had been waiting for someone to ask him -- and on Wednesday night, a reporter did.
McGwire doesn't condemn andro, a legal supplement. He just doesn't want youngsters to use it just because he has. It should be an adult choice, McGwire said.
"I still believe there's nothing wrong with it," he said. "But if I have a message for kids, it's that you don't necessarily have to follow what somebody who's in the public eye does. If you're an adult, you elect to choose your own destiny.
"I don't like the fact that some young high school kids think they need to do something to follow in the steps of a professional athlete ... but when you're an adult, you can make your own decisions. When you're young like that, you can make wrong decisions."
Androstenedione is a synthetic form of a male hormone that occurs naturally in the body and is converted to testosterone. Though sold legally over the counter and over the Internet in the United States, androstenedione is banned, as a performance-enhancing drug, by the National Football League, the National Collegiate Athletic Association and the International Olympic Committee.
Studies have shown that individuals with high levels of testosterone have more muscle mass, and some physicians, researchers and endocrinologists believe that andro should be reclassified as an anabolic steroid. Potentially dangerous side effects of steroids include heart disease and liver dysfunction.
But results of an Iowa State University study of 30 young men released June 1 found that andro did not help build muscle but did raise the risk of heart disease, pancreatic cancer and breast enlargement. That study was downgraded by doctors who believe it underestimated andro's danger because the test subjects took dosages smaller than what pro athletes routinely ingest.
Major League Baseball, adopting a neutral stance, is awaiting the results of a Harvard University study on the effects of androstenedione. Baseball's top officials have said they will neither condone nor discourage use of the supplement until the study is completed.
Critics have suggested that baseball is reluctant to tarnish McGwire's record by banning or discouraging the use of androstenedione. Baseball Commissioner Bud Selig and officials from the Major League Baseball Players Association dispute that contention.
And McGwire maintains that andro merely helped him have more efficient workouts but did not increase his strength. McGwire said there has been no difference in the quality of his workouts since he discontinued using andro. He said he isn't using an alternative supplement in lieu of andro and won't resume using andro.
Cardinals trainer Barry Weinberg said of McGwire: "He's gone about his business the same way. Mark's preparation is exactly the same as it's been for years. His work habits are still the same, and it all relates to his productivity. He's consistent in his life habits -- his eating, his nutrition, his workouts.
"What this is showing is the insignificance of something (andro) that's maybe been blown out of proportion."
Though his home-run pace has decreased slightly -- he homers every 8.5 at-bats this season, compared with every 7.2 at-bats last year -- McGwire has 42 homers and is contending for the major league lead.
"This shows that andro is irrelevant," McGwire said. "I've done this season what I've done my whole career. I've been saying it all along that you don't hit home runs because of andro. It's my hands and my eyes and my brain. There have been studies proving that it doesn't do anything to improve strength, anyway, which has always been my claim.
"I don't feel I need to prove anything. But this is for young children who think they need it. I elected not to take it. I don't need it; I don't want it."