Researchers from the Harvard Medical School and Cambridge Health Alliance in Massachusetts found that some dietary supplements sold in the United States contain a synthetic stimulant that hasn't been tested on humans.
Scientists and supplement industry officials warned users of workout, weight-loss and brain-function products sold by Amazon and GNC to check the labels for AMP Citrate. The compound is similar to DMAA chemical that the U.S. Food and Drug Administration (FDA) banned due to health complications, USA Today reported.
Study co-author Pieter Cohen from Harvard Medical School and Cambridge Health Alliance worked with his colleagues in examining 14 weight-loss and sports supplements for the presence of these stimulants. The laboratory tests revealed that the synthetic stimulant was present in 12 of the products they tested, at an average of 13 to 120 mg per serving. Researchers worried that people taking these products were not aware that one of the ingredients has only been tested in animals.
One of the products containing the stimulant was Frenzy, a pre-workout supplement, that has similar effects to those of Craze, a supplement that was banned after a methamphetamine-like compound was found in the ingredients.
Consumers buy these products because of the "endless energy," "extreme focus" and "tunnel vision" they get while taking them.
Other products that contain the stimulant are Contraband (made by Iron Forged Nutrition), Redline White Heat and MD2 Meltdown (made by Vital Pharmaceuticals Inc., which distributes the supplements under the brand name VPX), Evol and Decimate Amplified (made by Genomyx LLC), Oxyfit Xtreme and Synetherm (sold at planetarynutrition.com), AMPitropin and AMPilean (made by Lecheek Nutrition), OxyTHERMPro (made by deNOVOLABS) and OxyphenXR AMP'D (made by Beta Labs Ltd.).
"This is probably just a fraction of the supplements in the U.S. that contain this new designer stimulant," Cohen told Reuters Health.
Cohen explained that manufacturers could have decided to include DMBA in their products because, if taken in higher doses, it can create effects similar to those of DMAA, such as weight loss, bodybuilding, and other health-related changes.
Further details of the study were published in the Oct. 10 issue of Drug Testing and Analysis.
