HEALTHY TODAY | Cloudy days ahead

Early spring in the Puget Sound region is known for numerous cloudy and rainy days. While everyone knows that a hot, sunny, summer day can cause sunburns, many do not realize that 80 percent of the sun’s harmful rays penetrate through clouds and rain. Thus, a person can still burn on a cloudy day.

Risk of burning decreases in winter, but damaging rays still penetrate through drizzle, rain and clouds, increasing the risk of skin cancer and premature skin aging. In fact, skin cancer rates are as high or higher in Washington state than in sunnier states.

Harmful rays

Sunlight has two harmful types of radiation: ultraviolet A (UVA) and ultraviolet B (UVB). UVB rays cause sunburn, and UVA rays increase pigmentation and prematurely age the skin, causing wrinkles, brown spots and skin laxity. Both types of rays increase the risk of skin cancer.

Tanning beds contain mostly UVA (although some also have UVB) and have been proven to increase the risk of skin cancer.

About 2 million people develop skin cancer every year in the United States. The most common type is basal cell carcinoma, which can be disfiguring but not life-threatening.

Squamous cell carcinoma is second-most-common and may be life-threatening in 2 to 5 percent of those diagnosed.

Melanoma, the third-most-common skin cancer, has the highest rate of mortality. One out of five Americans will get a non-melanoma skin cancer in his or her lifetime. The incidence of melanoma is now one in 50, with 90 percent of these cases being directly related to UV exposure.

Protecting your skin

The American Academy of Dermatology and the Skin Cancer Foundation recommend that sunscreen be worn 365 days a year in every climate, if you spend any part of the day outdoors. This includes time spent in a vehicle, even with the windows up. Only UVA rays can penetrate window glass, so although you will not burn, premature aging and increased risk of skin cancer can still occur.

Sunscreen use reduces the risk of skin cancer by 50 percent. The American Academy of Dermatology stresses three important reminders before heading outside:

•Apply sunscreen 15 minutes before going outdoors, and reapply every two hours for continued sun exposure, especially when swimming or sweating.

•Seek shade; avoid exposure to sunlight between 10 a.m. and 2 p.m.

•Cover up as much skin as possible with protective clothing.

My patients often ask which sunscreen is the best to use and how to choose the right one. It is important to select one that you like and will use every day. This is a personal preference of how it feels, how easy it is to apply, how well it soaks in and whether it stings if it gets in your eyes.

Keep your sunscreen in a place where you will remember to use it daily.

In addition, make sure the sunscreen you choose has the following:

•Broad spectrum coverage for UVA and UVB rays;

•SPF (sun protective factor) of at least 30; and

•Water resistance.

Before you head outside on a sunny or a cloudy day this spring, apply an SPF 30 sunscreen to lower your risk of sunburns, premature aging and skin cancer.

BARBARA FOX, M.D., FAAD, specializes in dermatology at Pacific Medical Centers (www.PacMed.org). To comment on this column, write to MPTimes@nwlink.com.