CHICAGO -- Joseph Perez used to gear up for his intense workouts by taking ephedra-based dietary supplements. When they were banned because of safety concerns, Perez turned to an even more potent stimulant called DMAA.
Like ephedra, the DMAA supplements often left Perez feeling warm, energized and mentally focused.
"It's kind of like taking three cups of coffee," said the 35-year-old competitive bodybuilder and event promoter, who lives in Joliet, Ill. "It doesn't give you superhuman strength. It just gives you more mental drive to get you into the gym and get the job done."
But regulators and other critics are increasingly alarmed about DMAA's popularity as a preworkout energy booster and "fat destroyer." Though it is often marketed as a natural substance derived from geraniums, critics say there is no good evidence that is true.
Instead, they say, the chemical is the latest and most blatant example of a pharmaceutical compound masquerading as a natural ingredient, prompting calls for tighter federal oversight of dietary supplements.
The compound, also known as 1,3-dimethylamylamine or methylhexaneamine, was patented as a nasal decongestant decades ago and is similar in structure to ephedrine and amphetamine. It is now found in more than 200 products sold under brand names like Hemo Rage Black and Jack3d.
In people's bodies, DMAA acts like adrenaline, which is normally produced in times of stress, said Dr. Pieter Cohen, an assistant professor at Harvard Medical School and general internist at Cambridge Health Alliance.
"It's a potentially dangerous ingredient, and manufacturers' claims that it is naturally derived are unsubstantiated," said Cohen. In a recent commentary published in the Archives of Internal Medicine, Cohen called on suppliers to take all DMAA supplements off the market.
In late April, the U.S. Food and Drug Administration issued warning letters to 10 companies, saying the agency does not consider synthetically produced DMAA to be a "dietary ingredient" such as a vitamin, mineral or herb and that the companies had not provided evidence it is safe.
In fact, the FDA said, DMAA can narrow blood vessels and arteries, which can increase blood pressure and lead to shortness of breath, a tightening in the chest or heart attack.