Sun Exposure & Sunblock: Great Info For Your Patients
/
Importance of Sunscreen/Sunblock
I reviewed a Special Report insert in the April 2011 The Dermatologist journal that was very informative about the need and use of sun protection. It details the difference in effects of UVA vs UVB rays. I will summarize the main points. It is critical to educate patients about the following information.
UVA and UVB are the rays that are important in skin disease and aging. UVA comprises 96.5% of UV radiation and UVB comprises only 3.5%. (Remember that SPF only tells you how much of the UVB is blocked, although UVB is important in damage to the skin). UVA can penetrate glass and reach the skin’s dermis, while UVB cannot. UV radiation causes DNA damage, immunosuppression, and sunburn.
After UV exposure, melanin (pigment) synthesis is a mechanism to combat UV damage. Melanin blocks UV and scatters UV radiation to prevent damage. This is why darker skinned individuals do not sunburn as easily and do not show as much sun-induced aging and skin disease/cancer. UV-induced immunosuppression is associated with increased risk of skin cancer.