Protect your skin from the inside out
By Stacey Warde
P.F. Crockett, a 53-year-old building contractor who lives in California, has spent much of his life in the sun. Looking at his face, it appears he has been in a fight. And he has been in a battle of sorts, one that will continue for the rest of his years. His battle is with an insidious opponent: skin cancer, which, according to the National Cancer Institute, is the most common type of cancer in the United States.
More than 20 years ago, dry, dark spots began appearing on Crockett's face and shoulders, signaling actinic keratosis, a precancerous condition caused from overexposure to ultraviolet radiation from the sun. Since then, intermittently, he has applied a topical therapy, which causes damaged skin to peel off allowing healthier skin to take its place, forestalling the development of cancer.
With red hair and a fair complexion, Crockett is among a population whose coloring puts them at highest risk of skin cancer. Years of sun exposure—without proper protection—have further increased his vulnerability. From the time he was a baby, he spent summers on the beach with his family. "I'd get sick with sunburn year after year," he remembers. "When I was a kid, nobody knew about UV protection, or even what UV was," he says.
Today, however, we not only understand how dangerous ultraviolet (UV) rays can be and how important sunscreen is, but we are also discovering other methods to protect skin—from the inside out. Certain foods and nutrients can give you and your family another defense in the ongoing battle against UV radiation.
How High Is Your Risk?
To prevail against the threat of skin cancer, it's critical to understand UV radiation and to assess your risk. Although more people are aware of the potential hazards of UV radiation today, the prevalence of skin cancer—basal cell, squamous cell and the deadly melanoma—remains high and the threat real.
Current estimates suggest that 40 to 50 percent of Americans who live to age 65 will have skin cancer at least once. One million cases of curable basal and squamous cell cancers occur annually, according to the American Cancer Society. Yet, fortunately, in nearly 95 percent of these cases, early detection can result in successful treatment.
Melanoma, on the other hand, is a different story. This year, an estimated 53,600 people will be diagnosed with this form of skin cancer. Deaths from this disease, the seventh most frequent cancer in both American men and women, are estimated to be 7,400 annually. Like basal cell and squamous cell cancers, melanoma is also sometimes curable if caught early enough.
In most cases, the risk of skin cancer is directly related to the amount of exposure a person has had to ultraviolet light, most of which occurs during childhood, when long hours are spent outdoors. It's estimated that 80 percent of total lifetime sun exposure occurs before the age of 18. Experts agree: Protection is mandatory in childhood to prevent skin cancer later in life.
Fact: Snow, ice, sand, water and even concrete may reflect up to 100 percent of UV radiation. At greatest risk are people with lighter skin who work outside and live in areas with higher concentrations of UV radiation, specifically ultraviolet B (UVB) radiation, the most harmful type of UV wavelength (vs. ultraviolet A and ultraviolet C). In the United States, skin cancer rates are about twice as high for people living in the south than for those in the north. Higher elevations also up the risk: UVB intensity increases about 3 percent for every thousand feet in elevation.
To assess your geographical risk, the Environmental Protection Agency and the National Weather Service developed the UV Index, a measure that rates the level of UV exposure in 58 U.S. cities (see "Location, Location, Location: Geographical Risk").
Fact: While sunlight is essential for the body's production of vitamin D—a nutrient that works with vitamin A to build healthy bone structure and good eyesight—only a few minutes a day are required to provide optimum levels. Furthermore, use of some medications and herbs can increase sun sensitivity, requiring an even higher vigilance against UV rays. These include: certain antibiotics (tetracycline, doxycycline, sulfa drugs); psoralen compounds for treating psoriasis; thiazide diuretics (Diuril, Hydrodiuril); tricyclic antidepressants (Elavil); nonsteroidal anti-inflammatory drugs (aspirin, ibuprofen); some high blood pressure medications; certain acne medications; oral contraceptives; herbs such as St. John's wort (Hypericum perforatum), angelica (Angelica archangelica), and lomatium (Lomatium dissectum).
The surest way to protect against sun damage, of course, is to cover up. Dermatologists recommend thorough coverage. That means wearing hats with wide brims, protective clothing, and sunscreens with sun protection factors rated 15 or higher. Additionally, whenever possible, avoid sun exposure between 10 a.m. and 3 p.m., when the sun's rays are most potent.
Prevention Through Nutrition
Although researchers have long known that diet can alter or reduce the incidence of other forms of cancer, recent evidence suggests that diets low in fat and supplemented with selected vitamins and antioxidants also can help protect the skin. Here's why: Solar radiation interacts with skin cells, forming free radicals that can in turn cause genetic DNA mutations—the precursors of tumors. A diet that neutralizes these free radicals can counteract the sun's damaging effects.
Reducing total fat in the diet is one way to neutralize free radicals and help prevent precancerous skin conditions, according to a study conducted by Homer S. Black, MD, from the Baylor College of Medicine in Houston (New England Journal of Medicine, 1994, vol. 330, no. 18). Black divided patients who had previously suffered some form of nonmelanotic skin cancer into two groups. In the control group, no changes were made to the diet, which consisted of 36 to 40 percent fat calories. The second group reduced fat calories to 20 percent. Those in the control group were nearly five times as likely to develop premalignant skin lesions than those who lowered their fat intake.
"This is an area where people thought there'd be no relationship," Black says. "We have experimentally shown that high levels of dietary fat exacerbate the development of tumors caused by ultraviolet rays."
But what about the nutrients in that low-fat diet? Carolyn Katzin, a certified nutritionist in Brentwood, Calif., who has helped cancer patients develop nutrient regimens for nearly 16 years, believes a balanced diet rich in free radical-fighting vitamins, minerals, phytochemicals and carotenoids will offer the best nutritional protection from the sun's carcinogenic impact on skin cells.
Neutralizing tumor-inducing free radicals with antioxidant vitamins and minerals is key, namely vitamins C and E, as well as the mineral selenium. While not directly antioxidants, zinc, copper, and manganese are minerals that support the process of neutralizing free radicals.
The derivatives of vitamin A, called retinoids, also have been reported as a strong defense in the battle against skin cancer. In one study, patients who had suffered from more than 10 actinic keratoses, and fewer than three skin cancers, were given doses of 25,000 IU of vitamin A daily for five years. There was a significant reduction in the occurrence of squamous cell but not basal cell skin cancers (Cosmetic Dermatology, June, 2001). Foods exhibiting vitamin A activity include liver, carrot juice, sweet potatoes, pumpkin, spinach, red peppers and mangoes.
Many of these colorful fruits and vegetables also contain powerful carotenoids that effectively neutralize free radicals. Lycopene, for example, the carotenoid responsible for making foods pink or red (tomatoes, watermelon, guava, pink grapefruit) is a strong antioxidant that has shown promise in cancer prevention. Also, glutathione, the essential part of enzymes that protect the body from carcinogens, is helpful in the fight against free radicals. Glutathione-rich foods include asparagus, avocado, garlic, parsley, acorn squash, zucchini, tomatoes and other fresh, preferably organic vegetables.
Although taking supplements will provide your body with an antioxidant boost, Katzin believes getting these nutrients from organic, whole foods will provide the most benefit.
James M. Spencer, MD, associate professor in the department of dermatology at Mount Sinai School of Medicine in New York, notes the growing body of research connecting diet and UV protection. He points to two promising groups of chemopreventive, antioxidant agents derived from plants—polyphenols and isoflavones—that have also had favorable results preventing and, in some cases, reversing cell damage caused by erythema, the first noticeable stage of sun injury.
The polyphenols found in green tea are rich in antioxidant activity and have skin-protective qualities. In one study, skin treated topically with green tea extracts showed a reduced number of sunburn cells and protection of certain immunity-boosting cells (Journal of the American Academy of Dermatology, 2001, vol. 44, no. 3). The researchers concluded that green tea extracts reduced the DNA damage that formed after UV radiation.
Although the research focused primarily on topical applications, there is evidence that oral supplements provide cancer protection as well. Drinking several cups of green tea daily has been shown to limit damage to normal tissues exposed to chemotherapy and ultraviolet radiation damage (Journal of Cellular Biochemistry Supplement, 1995, vol. 22).
Another powerful source of chemoprotective polyphenols is extract of grape seed (Vitis vinifera), which also acts as a potent antioxidant, mopping up free radicals and stabilizing cell membranes.
Soybean isoflavones and red clover contain the compound genistein, which appears to provide another source of UV protection, thanks again to potent antioxidant activity. Spencer notes that genistein also has the ability to disrupt signal transduction pathways related to tumor promotion. He believes, however, that more testing is needed before this promising compound can be considered a convincing cancer-fighting agent.
And, as in all disease prevention, immunity plays a vital role. Not only does UV radiation cause skin cancer, it can suppress the immune system, acting as a one-two punch. Therefore, supporting the body with natural immune boosters—including echinacea (Echinacea spp.), beta glucan and mushrooms (shiitake, maitake, and reishi)—is also beneficial.
While nutrition can provide protection from the sun's harmful rays, notes Katzin, the skin "is sensitive to diet up to a point." Spencer agrees that we shouldn't rely on diet as the sole means of preventing skin cancer. Diet as a chemoprevention strategy, he says, is still needing a lot more research to determine just how large a role it can play in UV protection. "We know that all three types of skin cancer are caused by ultraviolet radiation," he says. "That's a fact." In other words, the best skin cancer prevention is to limit sun exposure.
Basking In Prevention
While building outdoors, Crockett is ever mindful of the relentless California sun. He exercises the utmost caution now, covering up, putting on sunscreen religiously. Every winter for the last eight years, when the sun isn't so intensely beaming its UV rays, he applies the topical medication that makes his face look as if he has just gone a couple rounds in the ring.
And always, he's adamant that his four children, ages 8 - 14, understand the hazards of UV exposure. The risk in his family, he knows, is very high. Besides his susceptibility to skin cancer, Crockett's older brother has had basal cell carcinoma removed from his skin.
Fact: Cloudy days offer little or no protection from UVB, the most dangerous type of sun radiation. Is he more careful with his own children than his parents were with him and his siblings? "Absolutely," says Crockett. "They don't go out of the house without first putting on sunscreen." He and his wife also make sure the family's diet contains the necessary antioxidants and nutrients to combat free radicals. None of his children, he adds, has ever had a sunburn. But, "They're like any kids. You have to stay on top of them. You have to remind them all the time to put on the sunscreen." And, of course, to eat their carotenoid-packed veggies.