Three types of radiation reach us from the sun. Visible and infrared light rays provide light and warmth. Ultraviolet rays are harmful. The sun’s ultraviolet (UV)
light falls into three wavelength bands: UVA, UVB, and UVC.
UVA RAYS have the longest wavelength and remain high in intensity all day. They penetrate through the epidermis and deep into the dermis, damaging newer cells.
UVA rays are very dangerous and can cause cancers and sensitivity reactions.
UVB RAYS have a midrange wavelength, and like UVA rays penetrate the epidermis and continue into the dermis. These rays break down the organization of skin
cells, causing wrinkles and broken blood vessels. They are highest in intensity from 10 a.m. to 2 p.m. and near the equator. Glass protects skin from UVB rays.
UVC RAYS have the shortest wavelength and are usually absorbed by the ozone layer. They are absorbed by the epidermis and can be very dangerous in large
amounts. As the ozone layer thins, attention will need to be paid to these UVC rays.
Tips for Protecting Your Skin from the Damaging Effects of the Sun
Whenever possible, stay out of the sun for long periods of time, especially between 10 a.m. and 2 p.m., when rays are strongest.
Protect exposed skin all year round. Wear sunscreen with an SPF (sun protection factor) of 15 to 30, depending on the season and length of exposure. Long-
sleeved shirts and wide-brimmed hats provide some protection. Remember, the sun penetrates through loosely woven and wet clothing very easily, so wear
sunscreen even when covered.
Avoid tanning beds. There is no such thing as safe tanning.
Wear sunglasses that wrap around the eyes and have 100 percent UV-blocking lenses. Most sunscreens are too harsh to use on the sensitive area around the eyes.
Select a sunscreen that protects against both UVA and UVB rays, sometimes labeled as broad-spectrum sunscreen. Many popular sunscreens will not adequately
protect your skin from these harmful rays.
Apply liberally—about one teaspoon of sunscreen to your face and at least one ounce (about a shot glass) to your body each day. The face and hands are high-risk
areas for cancer, so apply liberally to those areas.
If you have sensitive skin, use a cream-based product, and avoid sunscreens with tretinoin (Retin-A, Stieva-A, Retisol-A, Rejuva-A, Renova, Vitamin A acid),
which dries the skin. Look for a fragrance-free, hypoallergenic sunscreen if you have any allergies to skin products.
Waterproof and water-resistant sunscreens are good if you are involved in swimming or sports. Waterproof products work for ninety minutes; protection with
water-resistant sunscreens lasts thirty minutes. They need to be applied/reapplied twenty minutes before entering the water so that the product can bond with the
skin.
Those who work out of doors might need frequent application of a sunscreen with a high SPF.
UVA rays are reflected from all light surfaces, including water, sand, snow, ice, and even concrete.
Children younger than six months old should not wear sunscreen but instead be covered and kept out of the sun.
Exposure to the sun produces the formation of molecules in the skin called free radicals. These molecules attack healthy skin cells, damaging and interfering with
the production of new collagen. With the destruction of collagen fibers and hyaluronic acid molecules—both of which are responsible for preserving the volume
and resiliency of the skin—skin loses its firmness, resulting in wrinkles. The sun can also damage the eyes and affect the immune system. UV rays can damage
white blood cells and Langerhans cells, both essential to the skin’s ability to fight viruses and other diseases.
For more information and to learn of new developments in sunscreen protection, these Web sites, listed recently in a New York Times article, might prove helpful.
Environmental Working Group (lists products with UVA protection) http://www.cosmeticsdatabase.com
The Skin Cancer Foundation http://www.skincancer.org
American Cancer Society http://www.cancer.org
American Academy of Dermatology http://www.aad.org
British Columbia Centre for Disease Control http://www.bccdc.org
Sunscreen Application
Apply sunscreen at least once a day, and use an adequate amount of the product.
Clean the skin before application.
Apply to cool, dry skin twenty to thirty minutes before exposure. Cool, dry skin allows sunscreen to bind effectively. When sunscreen is applied to warm skin, the
open pores can become irritated, and rashes can develop.
Two applications help cover any missed spots.
Apply moisturizer and makeup over sunscreen.