Studies have shown that (-)-HCA can not only inhibit the synthesis of fatty acids and fats, but also reduce appetite and food intake, and ultimately play a role in reducing weight, in addition, (-)-HCA also has a good effect on appetite control. serotonin (5-HT) is a neurotransmitter necessary for many behavioral functions such as mood, sleep and appetite control, and it affects eating behavior and body weight. If the serum 5-HT level is increased, there will also be a decrease in food intake, weight loss and energy expenditure. (-)-HCA can significantly inhibit the reabsorption of 5-HT and increase the level of serum 5-HT.