In our daily life, we often encounter food allergies. For example, some people feel numbness in the mouth and itchy throat after eating mangoes; some people vomit and have diarrhea and skin rashes after eating seafood; some people have difficulty breathing, asthma, loss of consciousness or even shock after eating pasta. These are all symptoms of food allergy. Food allergic reactions can occur to any food. Common allergenic foods include milk, eggs, peanuts, beans, fish, shrimp and wheat. Symptoms can be widespread, such as gastrointestinal symptoms: nausea, vomiting, abdominal pain, bloating, diarrhea, mucus-like or dilute watery stools, and in individuals, allergic gastritis and enteritis, celiac disease, etc. Skin symptoms: skin congestion, eczema, itching, urticaria, angioedema, usually on the face, neck and ears. Systemic symptoms: severe allergic reactions such as headache, dizziness, rapid drop in blood pressure, respiratory distress, loss of consciousness, etc. Food allergy can occur in people of any age. Children are more prone to food allergy because of the tenderness of the digestive tract mucosa, high vascular permeability and poor barrier function of the digestive tract, and various food allergens easily enter the bloodstream through the intestinal mucosa. Food allergies are easily caused by legumes, followed by milk, eggs, fish, shrimp, apples, peaches, etc. At present, the main methods to prevent and control food allergy are: 1. Avoidance therapy. This is the most effective way to prevent food allergy. That is, not to consume food containing allergic substances, that is, after the clinical diagnosis or medical history analysis clearly determine the allergen, should completely avoid re-intake of food containing such allergens. For example, if you are allergic to milk, you should avoid all foods containing milk, such as ice cream, ice cream, cakes, etc. that have added milk ingredients. 2. Processing of food. By deep processing of food, you can remove, destroy or reduce the content of allergens in food, for example, you can destroy the allergens in raw food by heating, or you can improve the physical and chemical properties and composition of food by adding certain ingredients, so as to remove allergens. For example, adding lactic acid bacteria to milk to break down the lactose in it, so that the milk becomes yogurt, so that people with lactose allergy can also eat it. 3. Substitution therapy. Simply put, it means replacing allergic foods with related foods to which you are not allergic. For example, people who are allergic to cow’s milk can replace it with goat’s milk or soy milk. 4. Desensitization therapy. Food allergies cannot be treated by desensitization at present. In foreign countries, there are trials of peanut desensitization being carried out, but they have not yet fully entered the clinic and there are certain dangers. In addition, it has been found that there is a crossover between pollen and fruit allergy, for example, people who are allergic to birch pollen may be allergic to apples, and people who are allergic to artemisia may be allergic to peaches or other fruits.