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Sun Damage 101: What You Need To Know

Learn the basics of what classifies as sun damage and what your risk factors may be.

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Stop Damage Before It Happens

It’s hard to argue with the impulse to be outdoors in the summer. With the warm weather, bright sunshine and occasional gentle breeze, time at the beach, dinners al fresco and long runs along sunny paths are all favorite pastimes.

But with that extra sun comes another important consideration: extra attention to sun damage prevention. Unprotected exposure to the sun is the main cause of both premature skin aging and skin cancer. Prevention is key, as it is the only way to truly protect your skin. This starts with using product containing SPF, rain or shine.

Dr. Bonnie Mackool, M.D., M.S.P.H., assistant professor of dermatology at Harvard Medical School, advises her clients that when it comes to SPF, the higher the protection factor, the better. It’s important to be vigilant about re-applying, she says, especially when sweating or swimming during prolonged exposure to the sun.

“The signs of sun damage can and do start before any signs of skin damage,” Mackool said. “Freckles are sun damage. A tan is sun damage.”

Your skin can rack up damage any time it is in the sun without protection. Those getting a lot of sun over time, referred to as chronic sun damage, are at the highest risk. And use of tanning beds, Mackool said, “is an absolute disaster.”

Signs of sun damage include sunburn, fine lines and brown spots on the skin. It’s possible to treat some of these cosmetically. Special toners, usually containing glycolic acid, pigment-lightening serums and Vitamin C antioxidants can help reduce the appearance of brown spots. Sunscreen protects against additional sun damage, and for women, Mackool says that layering makeup over your sunscreen can actually help it last longer.

However, the most important result of sun damage to be on the lookout for is skin cancer. There are three main kinds of skin cancer: basal cell carcinoma, squamous cell carcinoma and melanoma. Mackool recommends being familiar with the appearance of the moles and bumps that can indicate skin cancer, and that anything abnormal or changing should result in a trip to a dermatologist.

“If you have to bring in more than one word to describe a feature, that feature is atypical,” Mackool said. “Knowing what your moles look like is important.”

Of the three, melanoma is the most deadly type of skin cancer. Its incidence in women is on the rise, Mackool said, which may be in part linked to the rise of tanning bed use. Dermatologists are especially on alert for melanoma because they have a limited amount of time to locate the cancer before it spreads throughout the body. Skin checks are vitally important, as are visits to the dermatologist and knowing one’s risk factors.

“Sunburn is a big one. If you have atypical moles or a lot of moles, that’s a risk factor. Having had, or having an outdoor job, lifeguard, camp counselor, baseball player, all of those professions have an increased risk,” Mackool said. “Tanning beds. Having red hair is a risk factor. All ages and all people are at risk for melanoma.”

For those active outdoors, especially runners whose exposure to the sun is prolonged, SPF prevention is key. Mackool says a broad spectrum of UV protection is important, as well as reapplication every two hours. Using clothing, hats and visors to block the sun’s rays is also an effective form of prevention.

Finally, Mackool recommends that if you’ve never been to a dermatologist, you should make an appointment for a skin check. From there, based on history and risk factors, you can determine what your appointment frequency should be.


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