Yes, you still need sunscreen on cloudy days

If you live in San Diego, you’re probably familiar with “May gray” and “June gloom.” These seasonal occurrences happen when cool surface temperatures off the Pacific Ocean meet the warm air above it to form a thick marine layer. Not only do the skies above the beaches become gray and gloomy, but the clouds creep inland and stubbornly block out the sun.

If you’re heading outdoors on one of these days, it’s only natural to want to skip the sunscreen. But don’t give into the temptation. Experts say you should protect your skin like you would if it’s sunny because you can still get burned.

Clouds don’t block dangerous UV rays

“We often equate a sunburn with it being sunny, but that’s not the case,” says Dr. Mona Mofid, a dermatologist with Sharp Community Medical Group.

Ultraviolet, or UV, rays — not the outside temperature — damage skin and cause a sunburn, even on cloudy and cool days. “Some of the worst sunburns occur on the cold ski slopes — a combination of the altitude and UV exposure — or on days spent fishing, exacerbated by the UV reflection off the water,” Dr. Mofid says.

The sun emits harmful UV light, also known as UV radiation, which is a carcinogen, Dr. Mofid says. It reaches the earth’s surface in various degrees depending on its proximity and angle to the sun.

“The ozone layer — which is being depleted — absorbs many of the harmful rays, and the clouds can block some of the sun’s UV light,” says Dr. Mofid. “But neither block all the harmful radiation, and people often get a false sense of security.”

According to Dr. Mofid, on average, a person's risk for melanoma, the deadliest type of skin cancer, doubles if someone has had more than five sunburns in their lifetime. “Even just one blistering sunburn in childhood or adolescence more than doubles a person's chances of developing melanoma later in life,” she says.

Protecting your skin reduces more than your risk of skin cancer

It’s common knowledge that use of sunscreen reduces the incidence of skin cancers. However, the National Cancer Institute reports that only about 30% of women and less than 15% of men regularly use sunscreen on their face and other exposed areas of skin.

“In addition to the risk of sunburn and consequently, the risk of skin cancer, ultraviolet radiation directly correlates to wrinkling and aging,” says Dr. Mofid. “It causes degradation of the elastin and collagen of the skin.”

Sun damage is one of the most common causes of crepey skin, when the skin takes on a thin, wrinkled surface resembling crepe paper and loses its elasticity. While it’s not the only cause, Dr. Mofid says the best way to avoid skin damage is by protecting your skin outdoors.

“It’s important to use daily protection in the form of sunscreen, hats and clothing while enjoying the outdoors,” Dr. Mofid says. “And avoid tanning salon booths.”

Tanning devices, she says, emit UV light at a rate several fold more damaging to the skin. Case studies have shown that a single tanning salon session can increase your risk of skin cancer by 75%.

How to relieve sunburn sting

If you find yourself with a sunburn, which is inflammation of the skin, during May gray, June gloom or any other time of the year, Dr. Mofid offers the following advice to help with discomfort:

• Soak in cool, non-chlorinated water to help soothe your skin. Add a few tablespoons of baking soda or a cup of oats to the bath to help the skin recover.

• Drink lots of water to rehydrate your body and skin.

• Wear loose clothing.

• Take over-the-counter anti-inflammatory medications, such as ibuprofen, to help decrease inflammation and relieve pain. (Talk with your doctor before taking these and other medications.)

• Apply aloe vera commercial products to soothe sunburn. The gel inside an aloe vera plant can also be effective.

• Use a numbing product, such as lidocaine, to help soothe and cool the skin.

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