Asian slimming supplements often packed with sibutramine

Researchers at the Polish National Medicines Institute are worried about the growing numbers of Europeans that are buying Asian supplements containing slimming herbs through the internet. According to their analyses, these products often contain dangerously high doses of sibutramine, or close relations of this risky chemical, without this being mentioned on the label.

A few months ago the Poles published analyses of supplements that had been confiscated by customs. Most samples came from the airport at Warsaw. The products in question were Meizitang [shown in the figure at the bottom of the page: 6], Meizitanc [2], LiDa Dai Dai Hua Jiao Nang [1], Super Slim [3], 3X Slimming Power [4], White Lion White Tea [above] and Miaozi [5].

The researchers examined 25 products in total. They determined whether the slimming supplements contained sibutramine, or the sibutramine analogues N-desmethylsibutramine and N-didesmethylsibutramine. [Structural formulas shown below.]

Sibutramine was available as a diet drug in the EU for a couple of years, but doctors no longer prescribe it as it causes cardiovascular disease in some people. N-Desmethylsibutramine and N-didesmethylsibutramine are designer versions van sibutramine. Untrustworthy supplements companies put these in their products because they know that the authorities can trace sibutramine. The companies hope that government labs won’t spot the designer varieties.

The sibutramine analogues work almost as well as sibutramine. N-Desmethylsibutramine actually works better than ordinary sibutramine. But then again the risk of side effects is greater with N-desmethylsibutramine than with sibutramine.

In 23 of the 25 slimming supplements the researchers found at times extremely high concentrations of sibutramine or N-desmethylsibutramine. The graph below shows the amount of mg sibutramines the Poles found per capsule in the slimming supplements.

Supplements 1-11: LiDa, supplement 12: Meizitanc, supplements 13-16: Meizitang, supplement 17: Super Slim, supplement 18: 3X Slimming Power, supplement 19: White Lion, supplements 20-23: Miaozi.