Expired beer may spoil and cause food poisoning. Beer is a fermented beverage, which is rich in amino acids, vitamins, alcohol, etc. After the expiration date, the substances contained in the beer may deteriorate and produce substances harmful to the human body, which may cause food poisoning after drinking. Drinking expired beer will stimulate the gastrointestinal tract, causing nausea, vomiting, abdominal pain, diarrhea and so on. Substances contained therein may produce toxins when they deteriorate, causing headaches, dizziness, nausea, etc. Beer contains alcohol, which has been classified as a class 1 carcinogen by the International Health Organization, and regular consumption of beer will increase the chances of developing digestive tract tumors. Therefore, try not to drink beer after the expiration date, to avoid causing food poisoning and health hazards, usually not recommended to drink alcohol.