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Sunscreens - The Most Important Part of Your Summer Wardrobe

Summer is here and the store shelves are overflowing with sunscreens.The labels can be confusing -- UVA, UVB, or broad-spectrum protection. SPF 15, 30, 45 or higher. What number should you use? While you may have heard this all before, it bears repeating, because skin cancer is preventable.

Washington University dermatologic surgeon, Eva Hurst, MD, says, “We continue to learn more about how ultraviolet light from the sun affects our skin. Historically, we’ve known that ultraviolet B rays (UVB) contribute to skin cancer. More recently, we’ve gained a better understanding that the ultraviolet A rays (UVA) also cause skin cancer, and are the main contributor to wrinkling and aging changes.”

Dr. Hurst adds, “The term 'broad-spectrum coverage' means a preparation protects across the sun's light spectrum -- against both UVA and UVB rays. Sunscreen makers are challenged to formulate sunscreens that give the best coverage and at the same time are aesthetically pleasing so
people will use them consistently.”

She says sunscreens can be divided into two types: physical blockers and chemical blockers.

“Physical blockers include preparations with zinc oxide or titanium dioxide. These reflect and block the sun’s rays. We used to associate these with “lifeguard white”, but newer preparations are
micronized and rub in colorless. They are still the best for children, people with sensitive skin, and those with skin allergies because they don’t contain a lot of preservatives. Physical blockers protect against both UVB and UVA.”

Chemical blockers work differently. They deactivate ultraviolet light, but tend to degrade over time. Because they have a thinner consistency, people like them better. Most chemical blockers protect against UVB rays. What we need to check, says Hurst, is that they also protect against UVA.

When selecting a sunscreen, read the bottle and check for the presence of one of three UVA protective ingredients:
  • oxybenzone
  • avobenzone (also known as Parasol 1789)
  • mexoryl.
Some sunscreens feature a combination of physical and chemical blockers. The sun protection factor (SPF) rating is based on UVB protection, but if one of the three ingredients above (oxybenzone, avobenzone or mexoryl) is included, the rating is broad-spectrum.

According to Dr. Hurst, “As far as SPF goes, you can’t go too high. SPF 15 may be adequate, but the problem is that most people don’t put enough on or cover all areas thoroughly. So we recommend an SPF of at least 30. If you’ve had a history of skin cancer or other sun exposure problems, go with an SPF of 45 or higher.”

Another important part of sun protection, especially for children, is sun-protective clothing. The average white tee shirt has an SPF of 4-8. Most people don’t know that. A better idea for sun exposure protection with lightweight UV clothing. It’s available in bathing suits, shirts, pants, hats -- in sizes for babies through adults.

Seven key tips:
  1. Use extra protection on water, sand, or snow. Don’t forget under the chin and ears. Your exposure is greater because of reflected sun.
  2. Even cloudy days yield significant UV exposure.
  3. Put sunscreen on 30 minutes before exposure, and preferably before you put on the swimsuit or shirts, so you don’t miss spots.
  4. Protect your lips. Lots of skin cancers occur on the lips, so use lip balm with at least an SPF 15.
  5. Don’t forget the scalp and head, especially if you have thinning hair. Skin cancers occur in part lines.
  6. Eyelids are a common location for skin cancers. Sunglasses for all ages are key to preventing eyelid cancer and cataracts. Make sure sunglasses block UV rays -- some don’t.
  7. Dont use tanning beds -- they amount to skin cancer in a box. There is no such thing as a protective tan. Tanning is a precancerous condition. Liquid or spray self-tanners are fine, but you still need a form of sun protection.
If you suspect you might have a skin cancer, Dr. Hurst is an expert in Mohs micrographic surgery. Mohs surgery removes skin cancers effectively, while taking the least normal tissue, for both a good clinical and cosmetic outcome. For an appointment, please call 314-996-8810.

Patients are seen at: 

Washingon University Center for Dermatologic and Cosmetic Surgery
969 N. Mason Rd., Suite 200
Creve Coeur, MO 63141
Washington University Physicians are the medical staff of  Barnes-Jewish Hospital and Children's Hospital - St. Louis Employment   About Us   Top Stories   For Your Protection      Site Map
Copyright 2013 Washington University School of Medicine
Copyright 2013 Washington University School of Medicine