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In recent decades, we’ve been taught that being out in the sun causes skin cancer, and that avoiding UV rays is the key to prevention. But that isn’t the whole story.
“All skin cancer is the result of damage to skin cells,” says Lise Alschuler, ND, who is board certified in naturopathic oncology and author of Five to Thrive: Your Cutting-Edge Cancer Prevention Plan. But contrary to popular wisdom, she says, not all the damage comes from the sun. In fact, most people are better off getting some sun rather than none, along with the right nutrients and non-toxic moisturizers.
The culprits that really damage skin are free radicals, or oxidants—molecules with a missing electron. To replace it, they steal electrons from other healthy molecules, which then become new free radicals that steal electrons from other healthy molecules, creating a harmful chain reaction known as “oxidation.”
This is the same process that causes an apple to turn brown or metal to rust. In our bodies, oxidation is a normal part of being alive, but it becomes dangerous when free radical levels rise too high. Too much sun is only one trigger. What we eat and what we put on our skin can also lower or raise our cancer risk by reducing or increasing oxidation.
The Beauty of Antioxidants
Antioxidants possess a unique ability to neutralize free radicals by donating an electron without themselves becoming damaged, so they can stop the chain reaction of oxidation. By doing this in the skin, they reduce predisposition to skin cancer. Plants contain many different types of antioxidants, but one specific type—flavonoids—is particularly beneficial for skin.
Plants need sunlight to grow, but they also need to protect themselves against damage from constant exposure to UV rays—and flavonoids do the trick. By eating plant foods, we absorb flavonoids that become active in our skin, protecting against the sun and other environmental damage.
In nature, there are more than 4,000 different types of flavonoids. They give vegetables and fruits their bright colors, and we can ingest a broad, healthful range simply by remembering to eat a wide variety of colors. Carotenoids, another type of antioxidant found in orange and yellow plant foods, also counteract UV damage to skin.
Supplements can offer additional protection. “The skin is a very vitamin-hungry organ,” says Alschuler. In addition, the antioxidants found in many topical products can also protect skin by increasing its antioxidant levels.
Healthy skin also needs a balance of essential fats: omega-3, found in deep-water fish, flax, and chia; omega-6 from plant oils; and omega-9 in olive oil. “Some research suggests that essential fatty acids may be preventative for skin cancer,” says Alschuler. A balance of fats helps reduce the chronic inflammation that triggers oxidation.
Moisture Protects Skin
Dry skin isn’t a cause of cancer, but it does weaken our natural defenses. “When skin isn’t well hydrated,” says Alschuler, “it uses antioxidants more quickly and is more prone to damage.” Solving the problem requires a two-pronged approach: inside and out.
For internal hydration, Alschuler recommends calculating your optimum daily water intake this way: Divide your weight (in pounds) in half, and drink at least that many ounces of water.
For a 150-pound person, that would mean drinking 75 ounces of water daily. Water-rich fruits and vegetables also count. As a benchmark, if you don’t need to urinate every two to four hours, you aren’t sufficiently hydrated.
On the outside, moisturizers can help keep skin hydrated by trapping moisture. In face and whole-body moisturizers, look for paraben-free products made with organic ingredients, as pesticides in plant ingredients will be absorbed by your body. Skip anything with “fragrance” or “parfum,” as these are synthetic scents that contain hormone disruptors and may be carcinogenic. If you like scent, choose products that contain essential oils. Avoid mineral oil, and instead choose shea butter, olive oil, or almond oil. Look for antioxidants, such as green tea, in moisturizers and other skin care products.
Sunscreens and Sun Benefits
There’s no doubt that getting burned by the sun, especially at a young age, increases risk for skin cancer, and according to the Mayo Clinic, people who use indoor tanning beds are 74 percent more likely to develop melanoma, the deadliest type of skin cancer. However, unless you’re particularly sensitive to the sun, getting a touch of color (not a burn) may be beneficial.
“Slight UV exposure triggers a healing response and activates vitamin D,” says Alschuler. Slight exposure—15–20 minutes without sunscreen, but preferably not during peak hours (10 am to 4 pm)—stimulates an antioxidant mechanism in the skin. Beyond that, use sunscreen.
Ironically, sunscreens that use chemicals to filter rays may be carcinogenic and, unless they are “broad spectrum,” may not stop dangerous UVA rays, which don’t cause a burn but penetrate and damage deeper layers of the skin. SPF ratings pertain only to burn-inducing UVB rays. The safest sunscreens contain zinc oxide or titanium dioxide. These ingredients act as a physical barrier, block both UVA and UVB rays, and are not carcinogenic.
THE UGLY TRUTH ABOUT SOME BEAUTY PRODUCTS
“There are a number of chemicals in everyday cosmetics that are linked to skin cancer,” says Nneka Leiba, MPhil, MPH, senior analyst at the Environmental Working Group (EWG), a non-profit organization that provides science-based information about toxins and advocates solutions. “Some of these chemicals are intentionally added to the product,” she says, “while others are contaminants or impurities that are released by other ingredients or introduced into products during the manufacturing process.” These, says Leiba, are some key chemicals to avoid:
Formaldehyde: A carcinogenic impurity, formaldehyde is released by a number of preservatives used in cosmetics. On labels, look for: Formaldehyde itself and the following preservatives: diazolidinyl urea, imidazolidinyl urea, DMDM hydantoin,
1,4-Dioxane: Another carcinogenic chemical, 1,4-dioxane was found to contaminate almost 50 percent of personal care products tested in 2008. 1,4-dioxane isn’t an ingredient listed on labels but an unwanted byproduct of processing. On labels, look for: PEG (polyethylene glycol) and ingredients that contain “eth.”
Retinyl Palmitate (a form of vitamin A): Frequently found in personal care products such as moisturizers and sunscreens, when used on skin that is exposed to sun, retinyl palmitate speeds the development of skin tumors and lesions. (Note: This is much different than taking vitamin A orally.) In 2011, the ingredient was found in two-fifths of sunscreens. On labels, look for: Retinyl palmitate.
For more detailed information, visit the EWG Skin Deep Cosmetics Database. It rates the safety of more than 69,000 items including sunscreens, cosmetics, and other skin, nail, and hair care products. Search by entering a product name at www.ewg.org/skindeep.