With the arrival of autumn, the weather turns cooler, the air humidity drops, and the skin dries out. Dry skin causes a decrease in skin barrier function and is susceptible to stimulation by many undesirable factors, accelerating skin aging and triggering or aggravating skin diseases. There is a sebaceous film on the surface of the skin, which together with skin cells and intercellular substances form a complete skin barrier. When the sebaceous film on the skin surface is lost and gaps appear, the skin structure is incomplete and the barrier function decreases, external harmful substances invade the skin. For example, bacteria, viruses, allergens (including detergents, cosmetics, pollen, sunlight, wind, dust, metals and other substances) enter the skin and produce lesions. At the same time, the skin loses too much water, the water-locking component is lost, the skin’s moisturizing function decreases, and the barrier function is weakened again. How to maintain the skin? We may want to do the following: 1, the skin is part of the human body, so first need to have a healthy body. In life, work and rest, proper exercise, nutritious diet, adequate sleep, optimism and calmness. 2, to avoid harmful factors on the skin. For example, avoid exposure to the sun, long time blowing wind, not in the dust, pollen environment for a long time, especially the face of people prone to allergies. In the dry autumn and winter, avoid excessive washing, hot water scalding skin, after bathing external application of moisturizing emollients. 3, proper maintenance. Choose the right skin care products, different age, different skin types, care methods are different: teenagers, the skin is oily, need to clear the acne system, including the ability to remove oil stronger cleanser, appropriate external toner, lotion. Young people, 20-30 years old, choose basic care products, pay attention to the balance of water and oil. after 30 years old, choose skin care products with strong water-locking ability, replenish skin nutrients, slow down the generation of wrinkles and lighten pigmentation. 4, the correct use of the mask. The mask has different functions, including further cleaning the skin, hydration, replenishment of nutrients, repairing the skin, enhancing the skin barrier function and so on. We can choose according to the need. Selection principles: Proper products, according to the skin type, to avoid misuse of poor quality products, especially for sensitive skin, choose pure quality products, if necessary, need to be under the guidance of a doctor. Some girls, like homemade masks, economical and interesting, can try, but need to be alert to allergies, after all, is not a mature product, not after professional processing. 5, when you encounter facial allergies, do not panic, sickness and anxiety. Some patients use hormone creams to apply topically to the face, which can temporarily reduce inflammation and relieve symptoms. However, hormone creams can only be used topically in moderation for a short period of time. Long-term topical application can cause facial skin atrophy, capillary dilation, lack of collagen, decreased skin barrier function, easier allergy and the formation of hormone-dependent dermatitis. Therefore, when facial allergy occurs, you should go to a hospital and be treated under the guidance of a doctor.