Among the many products advertised as fat burners, there are some that are effective at helping people lose weight, according to WebMD. One is an inhalant approved for asthma called formoterol, which researchers claim could help a 155-pound person burn about 200 extra calories per day without losing muscle.
However, the market is flooded with untested supplements advertised as fat burners, and some are dangerous. Products containing usnic acid have been linked to cases of acute liver disease and death, according to the Canadian Journal of Gastroenterology. The best strategy for those interested in weight loss supplements is to see a qualified medical professional.