Since most of the previous studies on the correlation between atopic dermatitis and food allergy only observed the rapid skin reactions and ignored the delayed eczema-like reactions, it is still controversial whether food allergy can trigger or aggravate the eczema-like skin lesions of atopic dermatitis. The prevalence of food allergy in children with atopic dermatitis is as high as about 40%, which is significantly higher than that of other children, so food allergy is extremely common in children with atopic dermatitis. 2. Food allergy is related to the age of the child with atopic dermatitis and the severity of the disease. The younger the age and the more severe the disease the stronger the correlation with food allergy. Therefore, only children under 3 years of age with persistent moderate to severe atopic dermatitis need to be tested for food allergies. Children with mild atopic dermatitis, especially older children, do not require significant time and expense to search for food allergens unless they have a previous history of suspected food allergy. Topical glucocorticoids and emollients may be more effective than dietary avoidance in these children. 3. Allergic foods associated with atopic dermatitis are mainly milk, eggs, wheat or soy, and about 75% of children are caused by these four foods, while a few children may be associated with peanuts, dried fruits or seafood [7J. For older children with pollen allergy, apples, celery, bananas and carrots are not to be ignored because of cross-allergy between pollen and certain vegetables and fruits. For these children, apples, celery, bananas and carrots are allergens that cannot be ignored. Since milk, eggs, wheat, soybeans, etc. are the most basic sources of protein for children, the identification of allergens must be accurate and must not be avoided blindly, otherwise it will lead to malnutrition in the affected children. 4. Food allergy in children with atopic dermatitis can be IgE-mediated, cell-mediated or a mixture of both, so clinically there are three types: non-eczema-like reactions, eczema-like reactions and mixed reactions. Non-eczema-like reactions are quick-onset IgE-mediated reactions that often appear within 2 hours of eating allergic foods and manifest as pruritus, erythema, pemphigus, and edema. This type of allergy is most common in children with atopic dermatitis. Eczema-like reactions are cell-mediated late reactions, often appearing hours or days after eating the allergic food, and manifesting as recurrence or exacerbation of eczema lesions, which are relatively rare. Mixed reactions can be seen with 2 of the above symptoms.