相比基因等不可抗因素,预防光老化是使皮肤保持年轻最简单和有效的手段。皮肤最外一层是表皮,皮肤的最里一层是下皮,夹在中间的是真皮。每一层皮肤当中都有含胶原蛋白纤维的结缔组织,使皮肤保持弹性和韧性。皮肤中的毛细血管负责输送养分,运走废物,汗腺能够帮助调节体温。皮肤中还有皮脂腺会分泌油脂,以防皮肤干裂。油脂还能够软化汗 Compared with other irresistible factors such as genes, the prevention of photoaging is the simplest and most effective way to keep the skin young. The outermost layer of the skin is the epidermis, the innermost layer of the skin is the epidermis, the middle is the dermis. Each layer of skin contains collagen fibers in the connective tissue, the skin to maintain flexibility and toughness. The capillaries in the skin are responsible for transporting nutrients and removing waste, and sweat glands help regulate body temperature. Sebaceous glands also secrete fat in the skin to prevent dry skin. Grease also softens sweat