The metabolism booster supplement is the latest miracle product to hit the fitness industry. We have all heard colleagues and friends complain that their metabolism has slowed down or ground to a crawl, allowing them to lose more weight or even lose weight for longer than ever before. All of us see the advertisements and commercials for metabolic boosters that promise to speed up your metabolism and promote rapid weight loss. So what is the metabolism booster? Why does it work? And are there any side effects?