After a routine skin check in 2000, I was diagnosed with a malignant melanoma, the most insidious of skin cancers. The phone call from my dermatologist with the initial news was one of those mind-bending times when life metamorphoses in an instant. In a deeply insensitive moment, the oncologist would say to me: “You know you did this to yourself, don't you?” When my tears started to well, he backpedaled vigorously, explaining that our generation, himself included, was guilty of unadulterated sun worship: the baby oil, the foil-covered reflective screens, the long SPF-free days at the beach. My cancer could, in fact, have been prevented.

We know that lighting up can lead to lung cancer, the top cause of cancer death in the United States, so stubbing out the cigarette is a no-brainer. But what about other cancers? Is it simply a case of bad genes and bad luck? Is it just a few renegade cells mutating and replicating at random? Increasingly, research suggests otherwise: How we live — what we eat, how active we are, how we choose to indulge during happy hour — impacts us at the cellular level. You might have a tumor-suppressing gene built into your DNA, for example, that gets switched off by environmental factors, opening a gate for abnormal cell growth. And while we'd all like to think the Big C won't happen to us, the stats are alarming: The average American has a 40 percent chance of developing cancer over a lifetime. On the upside, 80 percent of all cancers are related to lifestyle — diet, smoking, inactivity, and the like. You have little hope of changing your odds in Vegas — eventually you will lose at roulette — but if you can improve the odds of living cancer free, why not stack the deck in your favor?

Lose weight

In November 2007, the American Institute for Cancer Research (AICR) and the World Cancer Research Fund (WCRF) published a voluminous report — Food, Nutrition, Physical Activity, and the Prevention of Cancer: A Global Perspective — for which world experts analyzed 7,000 cancer studies. One of the most significant findings: Excess body fat is consistently linked to an increased cancer risk, specifically for cancer of the esophagus, pancreas, colon and rectum, endometrium, kidneys, and breasts. Adding to the evidence, a study published in The Lancet in February 2008 showed a link between obesity and at least a dozen cancers. Researchers found that an average weight gain of just 33 pounds in men increased the risk of esophageal cancer by 53 percent.

“There's an enzyme machinery in fat cells that leads to the production of hormones like estrogen, which plays an important role in the reproductive cancers,” explains David Schottenfeld, MD, MSc, professor emeritus of epidemiology and internal medicine at the University of Michigan and a member of the medical advisory board for the Prevent Cancer Foundation. The fat cells in an expanded waistline can also cause a state of chronic inflammation. “That smoldering inflammation can lead to the promotion of tumor growth,” says Schottenfeld. Researchers also point to insulin levels as another obesity-related cause of cancer. Bottom line: As the American population grows ever rounder, cancer rates are destined to rise.

Go easy on T-bones

Red meat — which means beef, pork, and lamb — does have its benefits. It's high in protein and iron. But it comes with a price tag. Red meat has been strongly linked to colorectal cancer, for one. “When red meat is exposed to high temps — frying, broiling, grilling — there's a chemical reaction that forms heterocyclic amines, or HCAs, which are known carcinogens,” explains Ann G. Kulze, MD, author of Dr. Ann's 10-Step Diet (Top Ten Wellness and Fitness, 2004). Another carcinogen lurks in your steak's charred crust: Polycyclic aromatic hydrocarbons result when the fat renders out and hits flame or smoke. “It's a hazardous fat-fire reaction,” says Kulze. If you just can't give up red meat, she recommends marinating and precooking it for two minutes in the microwave, trimming as much fat prior to grilling, and shaving off the charred bits afterward.

While you don't need to completely eschew the steaks and burgers (eating less than 18 ounces of red meat weekly is not associated with an increase in cancer risk), the AICR suggests eliminating nitrite-preserved processed meats altogether — any amount of which increases your risk of cancer. That means hot dogs, salami, ham, bacon, and sausage are out. “When you eat processed meat, the bacteria in your GI tract transform the nitrites into nitrosamines, a potent class of carcinogens,” says Kulze.

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