This week, researchers found that several over-the-counter supplements contain a synthetic version of a stimulant banned for inducing heart attacks, bleeding in the brain, and death. The supplements — which included Redline White Heat and OxyTHERM Pro — made promises to boost athletic performance, weight loss, and brain function.
The findings fuel a growing body of evidence criticizing the value of herbal supplements, including mystery ingredients and questionable efficacy. Given some 18 percent of Americans using them, experts are urging the F.D.A to enforce stronger regulations on herbal supplements and users to be duly cautious about what they put in their body. "Consumers are trying to be in better shape and better health, but putting themselves at unnecessary risk," says Pieter Cohen, a physician at Harvard Medical School. "No risk is worth it if we don't know if it works. We're seeing designer stimulants only studied in a chemistry lab being placed in a mainstream item, and people unknowingly consuming it." In the last year, researchers have found three designer stimulants in 18 different supplements including Craze, a pre-workout supplement found to contain a meth-like ingredient.
In the current study, Cohen and his colleagues in Michigan and the Netherlands found 13 to 120 milligrams of a synthetic stimulant called DMBA in 12 different over-the-counter supplements. DMBA has the same chemical makeup of DMAA — an ingredient banned by the F.D.A. in 2013. But DMBA may be even more dangerous than its model because its effects have never been tested in humans. In the only studies conducted on DMBA decades ago, it was found to have a similar effect on animals to amphetamine, meaning it could cause the same fatal adrenaline rush. According to the maximum daily intake listed for these supplements, customers would be consuming 26 to 320 mg of DMBA per day — an amount whose effects could be lethal.
Laws on what ingredients go into supplements are extremely lax, and the F.D.A. isn't cracking down on supplements anytime soon, says Cohen. Driven Sports, the same company that manufactured Craze, also produced one of the 12 supplements discovered to contain 210 mg. "It seems only after adverse health effects have been reported do we know there's a major problem," says Cohen. GNC recently pulled two of the supplements from its online store after the study's publication: Redline White Heat for workouts, and OxyTHERM for weight loss.
Whether it's weight loss, enriching your diet, or muscle building, Cohen says there are problems with any and all types of supplements, and you should avoid them altogether. There is currently no legal herbal combination for weight loss. "If a supplement claims it's all herbal and you're losing the pounds, there's something wrong," says Cohen. "It's either not going to work, or it is, and you're exposing yourself to dangerous stimulants." And as for workout supplements, those that promise to help build muscle have been found to contain compounds like increased testosterone, which can lead to heart attacks, strokes, and liver failure.
The only supplements Cohen advises could be reasonably safe are those that add protein to your diet and don't promise to give you a buzz — but only after you've tried increasing your protein with natural, healthy food. "There's not a whit of evidence that getting protein from a powder you buy at GNC works," says Cohen, leaving your best — and safest — bet to fueling your body naturally.