When the temperature drops, the oil secretion of sebaceous glands also decreases. In addition, the temperature difference between morning and evening in autumn and winter is large, the humidity in the air is low, and the moisture in the skin evaporates quickly. People will feel dry skin, especially the elderly. Because the sebum secretion function of sebaceous glands is reduced and the moisturizing effect is insufficient, the skin is more prone to dryness, roughness, desquamation and itching. At the same time, plus some external stimuli, such as excessive use of soap and washing powder. Therefore, it is recommended that you seek medical advice in time so as not to miss the best treatment period.