Sunscreen Q and A
The American Academy of Dermatology answers some common questions regarding sunscreen:
Q: What type of sunscreen should I use?
Sunscreens are available in many forms, including ointments, gels, lotions, sprays and wax sticks. The type you choose is a matter of personal choice. Creams are best for individuals with dry skin and for the face, but gels are preferable in hairy areas, such as the scalp or a male chest. Sticks are good around the eyes. There are also sunscreens for babies and sensitive skin. Ideally, sunscreens should be water-resistant and should have an SPF of 15 or higher that provides broad spectrum coverage against both UVA and UVB light.
Q: Can I use sunscreen I bought last summer?
Unless indicated by an expiration date, the FDA requires that all sunscreens be stable and at their original strength for at least three years.
Q: Does SPF 30 have twice as much sun protection as SPF 15?
UVB protection does not increase proportionately with a designated SPF number. For example, an SPF 30 screens 97 percent of UVB rays, while SPF 15 screens 93 percent and an SPF 2 screens 50 percent.
Q: How much sunscreen should I use?
Coat the skin liberally and rub it in thoroughly. Most people only use about 25 percent to 50 percent of the recommended amount of sunscreen.
Q: How often should I apply sunscreen?
Sunscreen should be applied 15 to 30 minutes before going outdoors. Sunscreen should be reapplied at least every two hours or after swimming or perspiring heavily. Even water-resistant sunscreens may lose their effectiveness after 40 minutes.