April 30th, 2012
F.D.A. Sends Warning Letters to 10 Marketers of ‘Workout Boosters’
By NATASHA SINGER and PETER LATTMAN
The New York Times
The Food and Drug Administration warned marketers of dietary supplements this week that certain popular “workout boosters” could increase people’s blood pressure, potentially causing shortness of breath or heart attacks.
With names like Jack3d and OxyElite Pro, these products have been popular with athletes because they contain an ingredient, known as dimethylamylamine or DMAA, advertised to increase energy, concentration and metabolism. Marketed as dietary supplements, the products have been best sellers among fitness buffs at stores like GNC and the Vitamin Shoppe, as well as on Web sites like bodybuilding.com.
But in warning letters sent on Tuesday to 10 firms that make or distribute such items, federal health regulators deemed the products adulterated because, the agency said, the firms had failed to demonstrate the safety of the crucial ingredient. DMAA, agency officials wrote in the letters, “narrows the blood vessels and arteries,” frequently leading to elevated blood pressure.