When spring comes, there is an increase in the number of patients with red, swollen and itchy skin in the clinic. Many of you will find that your skin will have this and that problem once spring comes, and you will often hear people complain, “I have sensitive skin and I am allergic to many things.” “My skin is allergic in the spring and has been for years.” Many people compare “sensitive skin” with “skin allergy”, but it’s not true. So, do you know the difference between sensitive skin and skin allergies? Sensitive skin refers to skin that has strong sensitivities and weak resistance and reacts significantly to various external stimuli. Skin allergy refers to allergic skin contact with allergens, redness, swelling, heat, itching and other manifestations. In short, sensitivity is a state, while allergy is a disease. Sensitive skin will react to most, if not all, topical skin care products, while allergic skin will only react to a specific allergen or allergens, and can still be replaced with other products when the skin allergy recovers. In terms of causes, there is a difference between congenital and acquired sensitive skin. The former is mainly related to genetics and skin type; the latter is mainly related to environmental factors, internal diseases, mental factors, improper maintenance, abuse of cosmetics and other factors that lead to reduced skin tolerance. The pollen, willow wool and dust mites in spring are all factors that may induce skin allergy. Therefore, in areas where pollen flies in spring, it is important to minimize going out to avoid causing pollen allergy. When you go out, you should do protective work, such as wearing masks and long-sleeved clothes. At the same time, in the choice of cosmetics, you must be very careful, and try to choose products that are softer in nature, have a single ingredient and are designed for sensitive skin. If you want to use a new cosmetic, you should first do a skin test by applying the cosmetic to the tender skin behind the ears and inner forearms, or to the actual site of use, and then observe the reaction after 3 to 5 days, and if there is an abnormal reaction, such as redness, swelling, rash, tingling, itching, etc., you must avoid using the cosmetic. In addition, attention should be paid to daily life and dietary regimen. For patients with photosensitivity, attention should be paid to eating less food such as cilantro, celery, mud snails, capers, rape, spinach, lettuce, marjoram, buckwheat and figs; avoid alcohol, spices, spicy food and coffee, strong tea, which are more stimulating to the skin. For people with sensitive skin, sun protection is best based on physical sun protection, and it is best to wear a sun hat and sunglasses when out in the sun.