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WLC Director of Nutrition Kathleen Zelman investigates the link between diet and cancer


Science is evolutionary, not revolutionary. While a new day often brings a new study looking at the link between cancer and diet, a single study rarely turns the world upside down. WebMD turned to experts to get to the bottom of the connection between cancer and nutrition. "The evidence on fruits and vegetables has weakened over the last few years with respect to breast cancer yet remains strong for other forms of cancer such as respiratory and gastrointestinal cancers," Tim Byer, MD, tells WebMD. "There is no doubt that a diet rich in fruits and vegetables continues to be beneficial for cancer prevention in general."

"Regular physical activity, weight control, and a heart-healthy diet are the best defenses for both men and women to prevent disease and promote a long and healthy life," says Byer, epidemiologist and professor of preventive medicine at University of Colorado School of Medicine.

Food, Genetics Interact

There are a whole host of benefits of a healthy diet that go beyond cancer. Fruits, vegetables, and whole grains -- the foundation of a healthy diet -- contain fiber, antioxidants, phytochemicals, and other healthy substances. These nutrient-dense foods are naturally fat free, very satisfying, low in calories, and the cornerstone of a weight-control eating plan.

Food interactions are very complex. Healthful substances in food continue to be discovered. Researchers are unraveling the mystery of exactly which components in foods are responsible for preventing cancer and other chronic diseases.

In addition to foods themselves, our own unique genetic profile determines how our body responds to health-promoting substances in foods. To get the health protection and disease prevention benefits from food, experts recommend eating a wide variety of plant-based foods.

Back to Basics

Years ago, the American Cancer Society moved away from making recommendations on specific foods to reduce cancer risk to an emphasis on improving dietary patterns."Clearly, some foods are more beneficial than others, and we continue to advocate five servings a day of colorful fruits and vegetables" Colleen Doyle, MS, RD, American Cancer Society nutrition and physical activity director, tells WebMD.

Doyle adds that physical activity and weight control are just as important as a diet rich in fruits, vegetables, and whole grains and limited in saturated fat.

The strongest evidence for cancer prevention lies in weight management and regular physical activity, according to Doyle. "Following the guidelines for alcohol (1 drink/day for women, 2 for men) and not smoking are also essential to wellness and disease prevention."

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