Aim for five to nine daily servings of all kinds of fruits and vegetables - especially these six superstars.
All cruciferous veggies (think cauliflower, cabbage, kale) contain cancer-fighting properties, but broccoli is the only one with a sizable amount of sulforaphane, a particularly potent compound that boosts the body's protective enzymes and flushes out cancer-causing chemicals, says Jed Fahey, ScD. A recent University of Michigan study on mice found that sulforaphane also targets cancer stem cells—those that aid in tumor growth.
Helps fight: breast, liver, lung, prostate, skin, stomach, and bladder cancers
All berries are packed with cancer-fighting phytonutrients. But black raspberries, in particular, contain very high concentrations of phytochemicals called anthocyanins, which slow down the growth of premalignant cells and keep new blood vessels from forming (and potentially feeding a cancerous tumor), according to Gary D. Stoner, PhD, a professor of internal medicine at The Ohio State University College of Medicine.
Helps fight: colon, esophageal, oral, and skin cancers
This juicy fruit is the best dietary source of lycopene, a carotenoid that gives tomatoes their red hue, Béliveau says. And that's good news, because lycopene was found to stop endometrial cancer cell growth in a study in Nutrition and Cancer. Endometrial cancer causes nearly 8,000 deaths a year.
Helps fight: endometrial, lung, prostate, and stomach cancers
Walnuts Their phytosterols (cholesterol-like molecules found in plants) have been shown to block estrogen receptors in breast cancer cells, possibly slowing the cells' growth, says Elaine Hardman, PhD, associate professor at Marshall University School of Medicine in Huntington, West Virginia.
Helps fight: breast and prostate cancers
Phytochemicals in garlic have been found to halt the formation of nitrosamines, carcinogens formed in the stomach (and in the intestines, in certain conditions) when you consume nitrates, a common food preservative, Béliveau says. In fact, the Iowa Women's Health Study found that women with the highest amounts of garlic in their diets had a 50 percent lower risk of certain colon cancers than women who ate the least.
Helps fight: breast, colon, esophageal, and stomach cancers
A study out of Michigan State University found that black and navy beans significantly reduced colon cancer incidence in rats, in part because a diet rich in the legumes increased levels of the fatty acid butyrate, which in high concentrations has protective effects against cancer growth. Another study, in the journal Crop Science, found dried beans particularly effective in preventing breast cancer in rats.
Helps fight: breast and colon cancers