As the population ages, common skin disorders demand greater attention. As the largest and most exposed organ of the body, the skin shows obvious and visible signs of aging. Induced by both intrinsic and extrinsic factors. Intrinsic aging is an inevitable physiological process that results in thin, dry skin, fine wrinkles, and gradual dermal atrophy, while extrinsic aging is engendered by
external environmental factors such as air pollution, smoking, poor nutrition, and sun exposure, resulting in coarse wrinkles, loss of elasticity, laxity, and rough textured appearance. Long-term exposure to ultraviolet irradiation from sunlight causes premature skin aging (photoaging), characterized in part by wrinkles, altered pigmentation, and loss of skin tone.
