The skin uses sunlight to help manufacture vitamin D, which is important for normal bone formation. But there’s a downside. The sun's ultraviolet light can cause major damage to the skin. The outer layer of the skin has cells that contain the pigment melanin. Melanin protects skin from the sun's ultraviolet rays. These can burn the skin and reduce its elasticity, leading to premature aging.
People tan because sunlight causes the skin to produce more melanin and darken. The tan fades when new cells move to the surface and the tanned cells are sloughed off. Some sunlight can be good as long as you have proper protection from overexposure. But too much ultraviolet, or UV, exposure can cause sunburn. The UV rays penetrate outer skin layers and hit the deeper layers of the skin, where they can damage or kill skin cells.
People, especially those who don’t have much melanin and who sunburn easily, should protect themselves. You can protect yourself by covering sensitive areas, wearing sunblock, limiting total exposure time, and avoiding the sun between 10 am and 2 pm.
Frequent exposure to ultraviolet rays over many years is the chief cause of skin cancer. And skin cancer should not be taken lightly.
Check your skin regularly for suspicious growths or other skin changes. Early detection and treatment are key in the successful treatment of skin cancer.
Review Date 9/7/2021
Updated by: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.