Promoting
sunscreen use is an integral part of prevention programmes aimed at reducing ultraviolet (UV) radiation-induced skin damage and
skin cancers. Protection against both UVB and UVA radiation is advocated. Most
sunscreens combine chemical UV absorbing
sunscreens and physical inorganic
sunscreens, which reflect UV, to provide broad-spectrum protection. Newer
triazole and
camphor-derivative based
sunscreens, also provide broad-spectrum protection and are more cosmetically acceptable than many traditional agents. Currently licensed
sunscreen ingredients in common use rarely cause allergic or photoallergic reactions.
Vitamin D levels are not significantly affected by regular use of a
sunscreen.
Sunscreen use reduces both the development of precancerous solar
keratosis and the recurrence of
squamous cell carcinomas.
Sunscreen use early in life may be important in prevention of
basal cell carcinomas. Increased
melanoma risk is influenced by the behaviour patterns of regular
sunscreen users, as opposed to any direct effect of
sunscreens. Sun protection factor (SPF) is affected by application density, water resistance and other factors. An adequate SPF for an individual should be balanced to skin phenotype and exposure habits. The correct use of
sunscreens should be combined with the avoidance of midday sun and the wearing of
protective clothing and glasses, as part of an overall sun protection regimen.