Hydroxycitrate is a stable form of hydroxycitric acid which is derived from the garcinia cambogia fruit preliminary research suggests that hca may be a useful weight loss aid hca has been demonstrated to reduce the conversion of carbohydrates into stored fat by inhibiting certain enzyme processes rresults confirm that hca reduces body weight and bmi suppresses appetite improves blood lipid profiles increases serum leptin and serotonin levels and increases fat oxidation more than placeb