Wrinkles are creases in the skin. The medical term for wrinkles is rhytids. Most wrinkles come from aging changes in skin. Aging of the skin, hair and nails is a natural process. There is little you can do to slow the rate of skin aging, but many things in the environment will speed it up.
Frequent exposure to sunlight results in early skin wrinkles and dark areas (liver spots). It also increases the chances of getting skin cancer. Exposure to cigarette smoke can also make the skin wrinkle sooner.
Read more at: https://medlineplus.gov/ency/article/003252.htm