Garcinia Cambogia is a small, pumpkin-shaped fruit, sometimes called tamarind. The HCA extract from garcinia cambogia supplement aids in weight loss by doing two things: It helps to block fat, and it helps to suppresses your appetite.HCA blocks fat by inhibiting a key enzyme that your body needs to make fat from carbohydrates: Citrate lyase. Usually carbohydrates or sugars that are not used immediately or stored in other forms are converted into fats. When HCA inhibits citrate lyase, the fat-making process is halted and the production of LDL (bad cholesterol) and triglycerides decrease. HCA also suppresses appetite by increasing serotonin levels. Serotonin is a neurotransmitter in your brain that makes you feel good. Its a target of many antidepressant medications. Having low levels of serotonin may make you feel depressed or anxious; it drives many people into emotional or reactive eating. By increasing serotonin levels, HCA improves mood and suppresses the drive to react to stressful situations with food.