Helps suppress your appetite, cravings, and prevents the absorption of fat by boosting your metabolism and increasing your energy. Finally, keep in mind that thermogenics aren't meant for a long-term use.Did you know that caffeine is often hidden in ingredients lists? Any supplement that includes ingredients like Mate, Guarana, Cola, Tea Leaf Extract, or Coffee Extract in it is going to have caffeine in it. In fact, the "extract" from those products is caffeine. They simply don't want to label it as caffeine because so many people are wary of the stuff. The three types of weight loss supplements are characterized by how they affect the body.