A new National Collegiate Athletic Association rule prohibits colleges from giving athletes muscle-building supplements such as creatine and androstenedione. Permissible supplements are carbohydrate-electrolyte sports drinks, energy bars, carbohydrate boosters, vitamins and minerals.

However, because the NCAA stopped short of banning the supplements, college players are allowed to purchase the substances themselves at health food stores.

“If it is natural, people think it is safe. Some products sold at health food stores can be very dangerous if manufactured poorly, used improperly or in higher concentrations than recommended,” said Leslie Bonci, director of sports nutrition at the University of Pittsburgh

Medical Center. “There are so many supplements infiltrating the market. Some contain unapproved drugs or contaminants that can cause great harm.”

Ephedra is one of the most controversial additives to several supplements on the shelves today. It affects beta-receptors in heart, Jalali said.

Ephedra is an ingredient sold in 200 unregulated dietary supplements and marketed as energy boosters and weight-loss aids. Ephedra supplements have been linked to side effects ranging from nervousness, anxiety, a fast heartbeat, high blood pressure and insomnia to kidney stones, psychosis, seizures, heart attack, stroke and death.

“Ephedra has an FDA warning, but it hasn’t been pulled from many health food shelves because it is a big seller,” Jalali said. “People need to carefully read all the ingredients in the supplements they take and make prudent decisions.”

Knowing what you are putting in your body can save your life. Your doctor is your best resource. Always remember, even if you don’t need a prescription to get a supplement, you should always let your doctor know that what you are taking.

Health professionals agree that adolescents under age 18 should not use creatine.

“There is rampant use of creatine in high schools,” Jalali said. “It increases performance, but we don’t have specific studies on this age group so I don’t recommend adolescents use it. Kids are better off getting on a diet program. They should drink mixes with protein powders, and nutrients and take base supplements like vitamins and minerals.”

A number of other groups are warning that use of creatine by teen-agers may be dangerous. Blue Cross and Blue Shield Association’s Healthy Competition Foundation said anecdotal evidence from physicians, coaches, trainers and athletes indicate a link between creatine use and several adverse reactions, including cramping, diarrhea, nausea, dizziness, dehydration, muscle strain, high blood pressure, incontinence, and abnormal liver and kidney functions.

According to Blue Cross and Blue Shield, a large number of high school seniors are using creatine monohydrate with little or no scientific evidence of its safety. One state high school federation in New Jersey is expected to recommend this year that its 440 members discourage athletes from using such diet supplements as androstenedione and creatine.

“Because there is a lack of [Food and Drug Administration] oversight, we are seeing an increasing trend of younger individuals having problems with these body-building supplements,” Lundblad said. “Most kids think it is OK to use these supplements because they are sold in stores.”

Another popular sport supplement that can be found on the shelves is androstenedione, a hormone that many athletes believe can be converted into the muscle-building male sex hormone testosterone. Andro achieved fame in 1998 when St. Louis Cardinals’ slugger Mark McGwire admitted he used it during his record-breaking 70-home run season.

But in a 1999 study, androstenedione did not increase the serum testosterone concentrations and there was no increased muscle strength or muscle size, according to the Journal of the American Medical Association. The study also found andro increased the risk of pancreatic cancer, Wollschlager said.

“Everyone should avoid all andro products,” Jalali said. “It seems to enhance testosterone levels, but the JAMA study questions this. It also enhances estrogen levels, which can have negative effects on men, such as water retention and breast formation.”