Metabotrim provides B vitamins and l-carnitine and chromium chelate. Chromium is important for normal insulin function, which regulates carbohydrate, fat and protein metabolism. L-Carnitine shuttles long-chain fatty acids into the mitochondria where fatty acids can be burned to provide energy. It is important for the oxidation (breakdown) of fat and needed for fat metabolism. Niacin (vitamin B-3) is involved in fatty acid synthesis. While Metabotrim does not "burn" existing fat, it does help metabolize fat, as it includes high levels of many ingredients already known to be involved in fat synthesis. This product works best when used in conjunction with a fitness plan, specifically aerobic activity.