Potential and limitations of topical sunscreens

Historical trends in sun exposure, the epidemiology of skin cancer and basic photobiology are reviewed with an emphasis on basic types and uses of sunscreening agents. Controversial topics reviewed include age of beginning sunscreen use, the possibility that sunscreens cause skin cancer and vitamin D deficiency, and whether a higher sun protection factor is better. Protection against ultraviolet A radiation, clinical problems with sunscreens, prevention of herpes labialis and the dermatologic implications of neonatal phototherapy are discussed.