Written by justis berg
30 June 2010

Weight-Loss Supplements are Thermogenic

Thermogenic supplements and drugs increase metabolism and fat use. They work by increasing the secretion of adrenaline (epinephrine), which speeds metabolism and puts the body on general alert. While many supplement makers claim that their products are thermogenic, few supply any evidence of their effectiveness. Danish researchers studied the thermogenic effects of common weight-loss supplement components such as caffeine, catechins, capsaicin, and tyrosine by blocking epinephrine release with drugs called beta-blockers. The supplements decreased metabolic rate by 25 percent following administration of the beta-blocking drug propranolol, which showed that they are thermogenic. The subjects experienced no decrease in appetite. Weight-loss supplements containing caffeine, catechins, capsaicin, and tyrosine work by increasing metabolic rate rather than by decreasing appetite. (Metabolism Clinical and Experimental, 58: 1137-1144, 2009)