Dark chocolate contains caffeine, which can excite human sympathetic nerves, make emotions excited, clear and agile, and eliminate fatigue and drowsiness. When the sympathetic nerve is stimulated and excited, it will suppress appetite. The cellulose in dark chocolate can promote intestinal peristalsis and help digestion. Isoflavones can inhibit the secretion of intestinal chloride ions and relieve diarrhea symptoms. Moreover, among all chocolates, dark chocolate has the lowest sugar content and fat content, but the caffeine content is higher than milk chocolate. Therefore, compared with milk chocolate, dark chocolate can help people avoid high-calorie holiday food more effectively and reduce people's desire for sweet, salty and fatty food. However, dark chocolate tastes bitter and not many people like it. ?