To understand how we visibly age, it helps to understand the anatomy of the skin. Two features many people recognize are hair follicles and sweat glands. The outer or superficial layer of the skin is called the epidermis. Underneath that, shown here in brown, is the dermis. The epidermis contains elastin, which gives young skin elasticity and enables it to quickly recover its shape. The sweat glands, which contain and release moisture, are also important for youthful skin, as is the blood supply. But a lot of unprotected sun exposure even when you're young can dry out the skin. Surface cracks allow even more moisture to escape. And damaged skin produces less elastin, which contributes to wrinkle formation. Using the right kind of sun block or sunscreen can help to prevent further damage.
The sun gives off several kinds of rays, including UVA and UVB. Both can damage skin. The skin on the left is protected from both, but the skin on the right is not protected against UVAs, which continue to damage tissues. This prompts cells in the epidermis to release melanin, which darkens the skin. A lot of exposure results in sunburn, which causes the release of more melanin to protect the skin and leads to sun spots and freckles. Using the wrong kinds of soaps can also age skin by stripping away the acid mantle, a thin coating that helps protect the skin surface against environmental factors such as wind and pollutants. Cigarette smoke reduces levels of nitric oxide--a cellular gas that helps keep skin flexible--which promotes skin cracks and wrinkles. Many women use an exfoliating agent to debride or scrape off dead skin cells. Some agents become smaller or dissolve as they're used, which can help prevent overuse or damage while still leaving young, healthy material. Hydration is also important; ideally, the solution will penetrate the pores and keep them small while also plumping up the epidermis.
Info: Dr Oz