There's no surefire way to eat to beat cancer. And while your overall diet is more important than eating a quota of fruits and vegetables, research shows these 6 foods may be particularly potent when it comes to cancer prevention.
Berries get their rich color from compounds called anthocyanins, which act as potent antioxidants in the body and shield cells from damage. Berries also contain ellagic acid and vitamin C. In laboratory studies, these compounds appear to stymie the growth of a long list of tumors, including those of the breast, cervix, skin, lungs and digestive tract. In one study, researchers from Georgetown University School of Medicine incorporated black raspberries into the diet of mice with breast cancer, and found that, after six months, their tumors were 70 percent smaller than those of mice on the control diet. People are not mice, of course, but promising findings like this have led to human studies with berry compounds. In one report last year, volunteers who ate blueberry powder daily (the equivalent of 12/3 cups fresh blueberries) for six weeks experienced rises in natural killer cells, an immune system component involved in fighting cancer.
1. Toss strawberries into a watercress or arugula salad.
2. Simmer blackberries or raspberries with a splash of water until they begin to break down. Swirl into plain yogurt.
3. Make a relish with chopped blueberries, orange zest, shallot and jalapeño. Serve with pork chops or fish.
Broccoli has long been a star in the cancer-prevention world, dating back to studies two decades ago that found an association between eating cruciferous vegetables and a lower risk of cancer. Further research found high amounts of potentially anti-cancer compounds in broccoli and broccoli sprouts. Crucifers—which include other members of the cabbage family, like cauliflower, Brussels sprouts and kale—have a complex chemical composition, so it's unclear what in particular is giving them their cancer-fighting power. They are rich in potassium, folate, vitamin C and a cocktail of phytochemicals, all of which might help. Lab studies suggest sulforaphane, a compound particularly abundant in broccoli, might make cells less susceptible to carcinogens (though frozen broccoli lacks this chemical).
Despite the numerous potentially cancer-killing compounds, studies in people haven't consistently found protection. But a 2013 analysis in the Annals of Oncology found that people who ate the most crucifers lowered their colon cancer risk by 18 percent compared with those who ate the least. Other studies have also seen reductions in risk for prostate and lung cancer.
1. Sauté chopped broccoli and thin slices of garlic in extra-virgin olive oil. Serve sprinkled with Pecorino Romano cheese.
2. Add kale to a smoothie made with frozen banana, apple, pineapple and plain yogurt.
3. Serve shredded cabbage instead of lettuce as a taco topper.
Beans are loaded with fiber and protein, which could help you feel full on fewer calories and, thus, lower your risk of obesity (and therefore cancer risk). Their fiber content feeds the healthy bacteria in the intestine and keep the cells lining the digestive tract healthy, minimizing cancer risk. They also contain folate—associated with reduced risk of colorectal, breast and other cancers. Whatever the reason, regularly eating legumes can be powerful, especially on cancers of the digestive system: in one study out of Loma Linda University, people who ate legumes at least three times a week cut their risk of colon cancer by 33 percent.
1. Make a creamy dip in your food processor with rinsed canned beans, extra-virgin olive oil, salt, pepper and dried herbs, such as thyme.
2. Toss drained chickpeas with corn oil and your choice of spice blend. Bake at 400°F until crispy and golden, stirring once or twice, 30 to 40 minutes.
3. Swap canned beans for half the ground beef to lighten up a meaty chili.
Tomatoes get their ruddy color from lycopene, which also makes grapefruit, watermelon and papaya pink. In animal studies, lycopene has been shown to protect against prostate and colorectal cancer. Though studies have been provocative, they have not been consistent in people. One of the latest studies, published last year in Cancer Epidemiology, Biomarkers & Prevention, reported that men who ate 10 servings of tomatoes a week (compared with men who seldom ate them) had an 18 percent lower risk of developing prostate cancer. Here's a twist for pasta lovers: go for the sauce, because studies suggest that eating cooked tomatoes may result in higher blood levels of lycopene than noshing on raw tomatoes or drinking tomato juice (cooking perhaps makes the compound more easily absorbed).
1. Dice watermelon, red onion and tomato; toss with basil, feta cheese and lemon juice to make a salsa.
2. Slow-roast halved plum tomatoes at 300°F for 2 hours. Serve, chopped, on toast as bruschetta.
3. Squeeze lime over sliced papaya. Sprinkle with chili powder and salt.
Pungent vegetables in this class include onions, leeks and chives, but garlic has been the standout for cancer protection. A review published last year in the journal Cancer Prevention Research concluded that the strongest evidence of cancer defense is for onions and garlic against digestive tract cancers—and other research suggests garlic lovers are less likely to develop pancreatic and breast tumors. However, there is not yet enough evidence to say exactly how much you need to eat to lower your cancer risk. And despite claims either way, research has not concluded whether eating garlic raw or cooked is best for fighting cancer.
1. Mash garlic and salt together and whisk into a vinaigrette.
2. Snip chives or scallions into scrambled eggs.
3. Caramelize onions until soft and golden and use as a topping for sandwiches or pizza.
One of the largest studies to look at the protective effects of eating nuts was published in November 2013 in the New England Journal of Medicine: those who ate 1 ounce of nuts at least five times a week were 11 percent less likely to die from any kind of cancer. Of particular interest are walnuts, which have been shown in animal studies to impede the growth of tumorcells. For example, one study in the journal Nutrition found walnuts inhibited the growth of colorectal cancer in mice. The reasons for the protective effects of nuts are still being studied, but researchers point to a number of compounds that appear to slow cancer, including resveratrol, ellagitannins, anacardic acid and omega-3 and -6 fatty acids.
1. Add chopped almonds or walnuts to chicken or tuna salad.
2. Grind almonds or pecans into crumbs in a food processor; use as "breading" for chicken cutlets.
3. Make chocolate bark: Melt dark chocolate, stir in your favorite nuts and spread on wax paper; chill until cold. Break into bite-size pieces.
Laura Beil is an independent journalist who writes about health and science. She lives near Dallas.
Photos by Leigh Beisch.
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