Hundreds of formulas are marketed for weight loss—touted to burn fat, boost metabolism, control sugar cravings, or help people overcome a genetic predisposition to obesity. But like all supplements, they are not subject to FDA review for effectiveness or safety.
Among the endless ingredients used are CLA, hoodia, capsaicin, hydroxycitric acid, and chitosan. Some, such as guarana, green tea extract, and yerba mate, are caffeine-like central nervous system stimulants that can increase blood pressure. Others such as cascara and senna are potentially dangerous herbal laxatives that can result in temporary weight loss by hastening the exit of waste from the intestines, while herbal diuretics like buchu and uva ursi can cause temporary water weight loss.
A few ingredients have been tested in controlled studies, with inconsistent results or modest effects at best. But most have no convincing scientific support behind them or have not been tested at all. And none are “clinically proven” for significant weight loss, no matter what their labels say. Save your money.
See also: Weight Loss Products #1 in Fraud.