The FDA says they contain unlisted ingredients, including powerful appetite-suppressing drugs and a suspected carcinogen.
A spokeswoman says in some cases, they have prescription drugs in amounts that greatly exceed their maximum recommended dosages.
The FDA says none of the supplements lists the dangerous ingredients on the label.
The pills are advertised as "natural" fat busters, and have names like Imelda Perfect Slim. Some suggest they are innovative
"herbal" remedies from Asia.
The FDA is considering criminal charges against some of the companies because they have not responded to requests for recalls.
The tainted weight loss products are:
Fatloss Slimming
2 Day Diet
3x Slimming Power
Japan Lingzhi 24 Hours Diet
5x Imelda Perfect Slimming
3 Day Diet
7 Day Herbal Slim
8 Factor Diet
7 Diet Day/Night Formula
999 Fitness Essence
Extrim Plus
GMP
Imelda Perfect Slim
Lida DaiDaihua
Miaozi Slim Capsules
Perfect Slim
Perfect Slim 5x
Phyto Shape
ProSlim Plus
Royal Slimming Formula
Slim 3 in 1
Slim Express 360
Slimtech
Somotrim
Superslim
TripleSlim
Zhen de Shou
Venom Hyperdrive 3.0
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