You can eat before the vaccination. Eating before vaccination will not affect the effectiveness of vaccination and will help the body to be in good condition for the vaccine to work in the body. In addition, for people with diabetes or a weak body, it can avoid dizziness and other uncomfortable symptoms caused by hunger. However, for eating before vaccination, you should be careful not to be too full. After vaccination, some people may have adverse gastrointestinal reactions, and being too full can easily cause nausea, vomiting, abdominal pain, diarrhea and other uncomfortable symptoms. In terms of food types, avoid eating spicy and stimulating foods, such as raw onion, ginger and garlic, because spicy and stimulating foods can promote blood circulation, dilate blood vessels and increase the permeability of blood vessels. These effects can easily lead to symptoms such as redness, swelling, hard nodules, itching and pain at the injection site, and also easily stimulate the gastrointestinal tract, increase gastrointestinal peristalsis and aggravate adverse reactions in the digestive tract. In addition, pay attention to avoid foods that can easily cause allergic reactions, such as mangoes, seafood, peanuts, cashew nuts, pineapples, etc. In addition, due to the special nature of some oral vaccines, such as polio vaccine, vaccine failure can occur when exposed to heat, it is recommended to avoid eating for 30 minutes before and after vaccination. It is recommended to adjust your work and rest schedule before vaccination, avoid staying up late and drinking alcohol, etc., so that you can adjust your condition to the best. After vaccination, medical observation should be carried out in the observation area for 30 minutes. If an allergic reaction to the vaccine occurs, which may be life-threatening in serious cases, timely treatment can be provided in the observation hospital.