The season when crabs are on the market in large quantities every year is also the season when persimmons are ripe, but crabs and persimmons are "enemies" on the dining table. Crab meat is rich in protein, and persimmons contain a lot of tannic acid. If they are eaten together, the tannic acid in persimmons can solidify the protein in crab meat into lumps, which are difficult to digest after eating and stay in the intestines for a long time. It can also ferment and putrefy, causing nausea, vomiting, abdominal pain, diarrhea and other discomforts