Crab and grapes can be eaten together. However, it should be noted that the edible part of the crab is rich in protein, and grapes contain ellagic acid, which can affect protein digestion and reduce the nutritional value of protein in case of large intake. In fact, some other foods such as persimmons, hawthorn, tea, spinach and so on contain tannic acid, although such reactions will not cause serious poisoning phenomenon, but can cause epigastric fullness, pain, burning sensation and other symptoms of indigestion. Crab belongs to the cold diet, eating a lot of crab may cause abdominal pain, diarrhea, high uric acid can also appear gout. Grapes belong to the higher sugar content of the fruit, although the role of digestion, but diarrhea eating grapes will increase the burden on the gastrointestinal tract, aggravate the condition. Protein consumption time in the human body is about 2-4 hours, it is recommended to eat crabs at least 2 hours before eating grapes, to reduce the chances of adverse reactions. In addition, as crabs are allergy-prone food, it is recommended to strictly select fresh crabs, cook them and consume them, avoiding dead crabs or cooked overnight crabs, as well as raw and pickled drunken crabs, so as to avoid causing gastrointestinal adverse reactions or bacterial infections.