Patients suffering from acne, seborrhea, seborrheic dermatitis, rosacea, and some infectious skin diseases should not consume too much sugar and fat. Because the occurrence of these diseases are mostly related to sugar metabolism and lipid metabolism, fatty and sugary foods can aggravate the condition. Some pruritic skin diseases such as psoriasis, pruritus, etc., the exact cause of itching is not well understood, but the intake of irritating food can stimulate the gustatory reflex arc, causing reactive vascular congestion, skin redness, increased itching, therefore, such patients should avoid chili, onion, garlic, ginger, strong tea, coffee, tobacco and alcohol; in addition, pruritic skin diseases should avoid eating fishy things such as seafood, fish and shrimp, beef and mutton; photosensitive Skin disease is often due to the consumption of mud snail, amaranth, rape, etc., and then the acute inflammatory reaction of the skin caused by sunlight exposure, so patients should avoid the above-mentioned food; herpes-like dermatitis patients should avoid eating kelp, nori and other iodine-rich food; long-term use of corticosteroids in patients with skin disease, to prohibit the consumption of pickled products, and promote a low-salt diet to reduce the side effects of hormone-induced sodium retention. If food allergy occurs, the lighter the whole body rash, itching, asthma, the more serious cause severe abdominal pain, vomiting, diarrhea, and even cause shock, life-threatening. The specific foods that should be avoided depend on individual circumstances. Usually, we take the food record method to find allergens. The food exclusion method is to eat light foods that are known to be non-allergenic for 3 weeks, then add a food every 4-5 days, and confirm which food caused the allergic symptoms by eating it. The food record method is to make a detailed record of the type and time of food eaten in relation to the occurrence of allergic symptoms, and to determine the allergen through analysis. It is generally important to pay attention to the diet in the 12-24 hours before the onset of symptoms.