Researchers are continually investigating foods that may help prevent cancer. But which ones have the strongest evidence?

The American Institute for Cancer Research (AICR), a nonprofit group that keeps tabs on cancer and diet research, recently identified the following foods as being among those having the strongest scientific evidence for fighting cancer…*


Under the hard rind, orange pumpkin flesh is rich in carotenoids such as beta-carotene, alpha-carotene, lutein and zeaxanthin. A high intake of foods containing carotenoids has been linked to a lower incidence of many cancers, including those of the esophagus, mouth and larynx. Scientists have recently uncovered another protective compound in pumpkins—cucurmosin, a protein that has been shown to slow the growth of pancreatic cancer cells.

Smart idea: Eat pumpkin (plain, canned pumpkin is a convenient option) and the seeds.

What to do: Eat a handful of pumpkin seeds (store-bought are fine) daily as a snack. To prepare your own, rinse fresh seeds in water, air-dry, add a touch of oil and bake at 350ºF for 10 to 20 minutes.


Grapefruit is a rich source of dietary fiber and vitamin C. The pink and red varieties also contain carotenoids (such as beta-carotene and lycopene) that decrease the DNA damage that can lead to cancer.

Scientific evidence: Strong research shows that foods like grapefruit help reduce risk for colorectal cancer. Other evidence suggests that it reduces risk for such malignancies as those of the esophagus, mouth, lung and stomach.

Helpful: Put red or pink grapefruit slices in a green salad with avocado. The tart grapefruit and creamy avocado are delicious together—and the fat in the avocado boosts the absorption of lycopene.

Caution: Grapefruit contains furanocoumarins, compounds that block a liver enzyme that breaks down some medications. (More than 85 medications interact with grapefruit, including cholesterol-lowering statins.) If you’re thinking about eating more grapefruit and currently take one or more medications, talk to your doctor first.


An apple a day is good for you—but two may be even better!

Scientific evidence: In a study published in the European Journal of Cancer Prevention, people who ate an apple a day had a 35% lower risk for colorectal cancer—and those who ate two or more apples had a 50% lower risk.

Apples are protective because they contain several anticancer nutrients (many of them found in the peel), including fiber, vitamin C and flavonoids such as quercetin and kaempferol—plant compounds that have stopped the growth of cancer in cellular and animal studies. Research does not specify any particular type of apple as being more protective, so enjoy your favorite variety.

A quick and easy apple dessert: Core an apple, stuff it with raisins and cinnamon, top the stuffing with one tablespoon of apple cider or water, cover the apple with waxed paper and microwave for two minutes.


When it comes to preventing cancer with diet, it’s not only what you eat—it’s also what you don’t eat.

Scientific evidence: The evidence is convincing that eating too much red meat is linked to colorectal cancer. The AICR recommends eating no more than 18 ounces a week of cooked red meat (such as beef, pork and lamb).

A cancer-fighting meal extender: An easy, delicious way to lower your intake of red meat is to replace some of it in recipes with mushrooms. They’re a perfect meat extender, with a savory, meaty taste and texture. What to do: In a recipe that uses ground meat, replace one-third to one-half of the meat with chopped or diced mushrooms.

In a recent study, people who substituted one cup of white button mushrooms a day for one cup of lean ground beef consumed 123 fewer daily calories and lost an average of seven pounds after one year.

If you’re heavier than you should be, losing weight means decreasing cancer risk—the AICR estimates that 122,000 yearly cases of cancer could be prevented if Americans weren’t overweight or obese.

*The studies cited in this article are only a small portion of the research supporting these cancer-fighting foods. The AICR and its international panel of experts review a much larger spectrum of research.