What You Need to Know About Sun Exposure and Skin Cancer

You hear the same advice every summer: slather on sunscreen and limit your time in the sun. Those rules still apply, but not everyone is getting the message.

Skin cancer is the most common type of cancer in the United States, according to the Skin Cancer Foundation; one out of every five people will develop skin cancer before the age of 70. Over the past three decades, skin cancer rates have gone up. Between 2011 and 2019 alone, rates increased by 31.5 percent. What’s behind the rise?

“The overall increase in skin cancers has to do with cumulative sun exposure combined with lack of adequate sun block or protection from UVA/UVB rays,” says Dr. Ava Shamban, a board-certified dermatologist in Los Angeles, California.

It’s time to get smarter about your sun exposure. Here are five things you need to know about sun exposure, according to a dermatologist, plus tips for enjoying the sun more safely.

1. Wearing Sunscreen Every Day of the Year Is a Must

You may not think about wearing sunscreen when it’s cloudy or rainy or even during winter. Yet you should. Why?

“The most harmful ultraviolet rays are present every day,” Shamban says. “They don’t retreat in winter and can filter through dark cloud coverage, which is why any uncovered areas of the body at any time of the year are exposed and vulnerable to the damage of the sun’s UV rays.”

Dermatologist-approved tips:

• Lather on sunscreen after you shower: make sunscreen application as much a part of your daily routine as brushing your teeth. Choose a broad-spectrum sunscreen that protects against UVA and UVB with an SPF of at least 30 and slather it on when you get out of the shower in the morning, as you would lotion.
• Put it on areas likely to be exposed to sunlight: this includes your legs, arms, shoulders, décolletage, neck, face, ears, and hands. The American Cancer Society also suggests a lip balm with sunscreen. You might even add a hand cream, moisturizer, or makeup with sun protection to your daily routine. These won’t replace sunscreen but will offer added support for vulnerable areas that are never covered in your reapplication plan, Shamban says.

2. One Bottle of Sunscreen Should Only Last You a Couple of Months

How quickly you go through that sunscreen depends not only on how big the bottle is but also on how well you’re applying it. In general, though, aim to go through at least one bottle during the summer, more if you’re sharing that bottle with others. If your bottle lingers, it’s a sign you’re probably not using enough.

Dermatologist-approved tips:

• Measure one ounce of sunscreen: The Skin Cancer Foundation recommends applying an ounce of sunscreen to your face and body. That’s about the size of a shot glass; for easy reference, keep a shot glass in your bathroom to help you measure it, Shamban says.
• Don’t skip your face: Your face alone should get a nickel-sized amount, says Dr. Adele Haimovic, a dermatologist based in New York. You should then reapply every two hours, she says.
• Don’t use expired sunscreen: Just watch those expiration dates, as sunscreen breaks down over time. “I’ve seen people who have gotten burns because they used expired sunscreen,” she adds. Once a year, go through all your sunscreens and toss any that have expired.

3. Skin Cancer Around the Eyes Is More Common Than You Think

Although any exposed skin may be prone to developing skin cancer, the skin around your eyes is particularly vulnerable because it’s thin and delicate, Shamban says. Roughly five to 10 percent of all basal cell carcinomas occur on the eyelids.

Dermatologist-approved tips:

• Wear polarized sunglasses: While you should always wear sun-protective eyewear when outdoors, choose a darker, polarized lens rated for ultraviolet protection; most sunglasses don’t have enough UV protection alone.
• Toss on a hat: If you don’t have polarized glasses, opt for a wide-brimmed hat that gives you at least three inches of shade. You can also use an umbrella to limit sun exposure.
• Consider alternative sun care products: Sunscreen is crucial, but if it bothers your eyes and causes a stinging sensation, use a mineral version, one containing zinc oxide and/or titanium dioxide, Haimovic says. You can also try a fragrance-free sunscreen for sensitive skin. Alternatively, use a protective powder with an SPF rating for your eyelids; try a stick formula or one with a “doe foot” applicator, which allows more precise application versus your finger, Shamban says. A broad-based sun-protection eye cream will also do the trick.

4. UV Light Can Penetrate Through Windows

Being by windows can give your mental health a boost, but know that those windows, whether in your home, office, or car, will expose you to harmful UV rays. There are two types of rays—UVA and UVB—and each one affects the skin differently. UVB rays are the classic burning rays, the most common cause of sunburns and the type most associated with skin cancer, says Haimovic.

Meanwhile, although UVA rays can cause sun damage and also lead to skin cancer, they’re associated more with aging, and it’s these rays that penetrate more through windows. “Most glass does not protect against UVA exposure,” Shamban says, adding that while some of the UVB rays get through, all of the UVA rays do. That’s one reason year-round sunscreen is so critical on exposed parts of your body.

Dermatologist-approved tips:

• Buy UV protection shields for car windows.
• Clothing can even add another layer of protection.
• Look for detergents that wash sun protection into your clothing.

5. Training Outside Increases Skin Cancer Risk

While this may be a no-brainer, it’s worth repeating: if you’re logging the miles outside, you’re at an increased risk of skin cancer.

• Reapply often: because you’re sweating so much sunscreen off, you  ‘ll need to reapply more frequently if you’re training outside.
• Avoid the brightest times of the day: plan your workouts so you’re not outside when the rays are at their strongest, generally between 10 am and 4 pm.

Bottom line? “Even if the sun doesn’t shine, it’s not a free pass from sun protection,” Shamban says. “Ultraviolet rays don’t take a vacation, and skin cancer knows no season.”

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