Your Ultimate Summer Skincare Guide

We've all heard over and over about the dangers of skin cancer, but when the warm weather arises, one can't lock herself indoors all summer. How best to prevent illness - and aging? We'll break it down.

SCREEN SAVERS
Sunscreen bottles are getting a face-lift this year, due to new FDA regulations that require both UVA and UVB protection labeling. Why isn't good old SPF enough? This number measures only UVB, which is partially responsible for sunburn, discoloration, and some skin cancers. Longer-wavelength UVA rays penetrate deeper, contributing to wrinkles and melanoma, the deadliest type of skin cancer, according to American Academy of Dermatology (AAD) President Elect Dr. Ronald Moy. "We're now finding that UVA may be as or more carcinogenic for melanoma," he says. "Tanning beds are pure UVA. More young women have skin cancer from using them."

What's inside the bottle is also getting an update, with new liquid formulas (perfect for oily summer complexions) hitting shelves now. But note that these typically contain chemical sun filters, and if your skin is extra sensitive or already slightly charred, anti-inflammatory zinc oxide can help soothe irritation while physically blocking UVA and UVB, says New York City dermatologist Dr. Anne Chapas. "As chemical sunscreens [like Parsol 1789, Oxybenzone, Homosalate, Octocrylene, and Octisalate] absorb UV light, they're also breaking down," explains Chapas, who prefers physical blocks because they don't need to be reapplied as often.
Chapas also suggests boosting your block potential with antioxidants. "They play a key role in reversing sun damage," she says. However, new research presented at this year's AAD meeting shows that some antioxidants can become harmful when exposed to sunlight, magnifying UV damage instead of diminishing it. One safe and effective antioxidant is vitamin E, which is naturally secreted by the body (in sebum) to protect the skin and is a key ingredient in Neutrogena's Helioplex360 (found in its Spectrum+ and Age Shield+ Repair SPF 55) and Coppertone Sport With Replenishing Antioxidants sunscreens.

DAMAGE CONTROL
"Wrinkling, freckles, skin thinning-everything we associate with aging is really sun damage, which is essentially DNA damage," explains Moy. "After someone goes tanning, you can measure DNA damage by testing the amount of toxins excreted in their urine." When you're 20, DNA repair enzymes in your skin are doing their job, but these enzyme levels drop as you get older. Moy suggests supplementing your body's own supply with serums and creams fortified with DNA repair enzymes from natural plant sources like plankton. "Within hours, you can measure the results of putting more on your skin," says Moy.

Previous post-sun regimens relied heavily on microdermabrasion and acid peels to remove dry, discolored, "damaged" skin, but there's not enough evidence to show that it repairs DNA, says Moy. "Exfoliation temporarily makes the skin look better, but the FDA is now investigating whether repeated peeling makes you more susceptible to deeper damage." He also cautions that certain active ingredients can negate a sunscreen's efficacy, making you more vulnerable. "If you put on benzoyl peroxide with sunscreen, it will inactivate the protection. Glycolic acids with sunscreens could have bad effects, too. We can't explain why we're seeing so many skin cancers now. Sometimes doctors blame it on lifestyle or ozone depletion, but it could be because of the products we've recommended for the past 20 years."

VITAMIN D-DAY
If it seemed like everyone suddenly became vitamin D deficient overnight, that's because new research linking its low levels to everything from heart disease to depression has forced physicians to re-evaluate daily requirements. Turns out, vitamin D isn't actually a vitamin but a hormone the skin produces when exposed to sunlight.

"Having low vitamin D is like not having enough insulin or thyroid hormone. It's a disease state," explains Los Angeles endocrinologist Dr. Sarfraz Zaidi, author of Power of Vitamin D. In the past decade, we've discovered that vitamin D does more than just help with calcium absorption and healthy bone maintenance; it helps with the natural turnover of cells. D deficiencies slow down cell death, so damaged cells linger and can mutate into tumors and cancer, Zaidi adds.

The old daily requirement of 600 international units (to prevent osteoporosis and rickets) is not enough to protect you from this deficiency, but don't start sun-worshipping just yet. A new recommended dosage has not been established because, like thyroid hormone or insulin, vitamin D is not a one-size-fits-all pill. "There has been a lot of research from Boston University professor Dr. Michael Holick about the importance of UV exposure for vitamin D, but he's funded by the tanning industry," says Chapas.
Aside from Holick and his followers, most doctors don't think the risk of skin cancer is worth the extra sun exposure (sunblock blocks vitamin D as well). Instead, Zaidi suggests supplementing with vitamin D3 pills. Ask your doctor for a 25 Hydroxy vitamin D test to find out if you're deficient.

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Reprinted with Permission of Hearst Communications, Inc.