Few things are as scary as being told, “You have cancer.” The good news is you can take steps to reduce your chances of ever dealing with the big C. Lessening your risk of developing cancer lies in living a healthy lifestyle—especially sticking with a health-promoting diet.
Certain nutrients and foods have been shown to boost immunity, reduce systemic inflammation and otherwise lessen your risk of hearing bad news after a checkup. In addition to proper nutrition, recommendations from the World Cancer Research Fund (wcrf.org) and the American Institute for Cancer Research (aicr.org) for reducing cancer risk include being active 30 minutes every day and staying within a healthy body weight.
Here’s what the latest studies and experts suggest to keep the body’s cancer defense systems in prime working order.
Eat plants. It’s the first item on our list for a good reason: Eating a plant-based diet rich in fruits, vegetables, legumes, grains, nuts and seeds goes a long way toward reducing your cancer risk. According to a 2013 study in JAMA Internal Medicine that followed, over 12 years, the habits of Seventh-Day Adventists—35% of whom are vegetarian versus 4% of the general population—people who eat plant-based diets live longer and have fewer cancer occurrences. They also develop less heart disease and weigh less.
“It’s most important to eat a whole food, plant-based diet and avoid animal protein,” says Maggie DiNome, MD, director of the Margie Petersen Breast Center at the John Wayne Cancer Institute, Providence Saint John’s Health Center in Santa Monica, California, who became a vegan five years ago.
Evidence shows a 15% to 20% increased risk of cancers of the colon and/or rectum for every 100 grams of red meat or 50 grams of processed meat (such as cold cuts) eaten per day, according to the American Cancer Society’s 2010 Nutrition Physical Activity Guidelines Advisory Committee. Cancer risks are higher for processed meats—the AICR says possible mechanisms may include the smoking process and additives such as nitrites—but experts suggest limiting or eliminating both types to best reduce risk.
If it’s too difficult to eat vegan all of the time, try to limit the animal portion of your diet to 10% or less and you’ll get the most cancer-reduction benefits. DiNome says, “We’re not sure why, but something about animal-source protein stimulates tumor growth that we don’t see from plant-based protein.”
If you’re eliminating animal protein you’ll need to get your protein from other sources. “Don’t try to make the change all at once,” DiNome advises. “Start out with one day a week or a weekend without eating any animal foods. If you’re concerned about protein requirements, consider that other countries have significantly lower percentages of their calories from protein and they don’t have as much heart disease and diabetes as we do.” Instead of meat, substitute vegetarian protein sources such as lentils, beans and nuts, as well as tofu and other soyfoods, including edamame (immature soybeans in the pod). Many seeds, including hemp and chia, also supply protein.
DiNome recommends getting 10% to 15% of your calories from protein. For example, if your diet consists of 2,000 calories, 200 of those calories should be from protein, or about 50 grams (a gram of protein equals 4 calories). Or simply limit animal protein to one out of every 10 meals.
What’s more, biologically active compounds called phytonutrients found in the allium group such as onions and garlic, as well as in citrus fruits, provide defense against cancer cell development, according to Monique Richard, RD, a Tennessee-based nutrition consultant. “They work by supporting the body’s ability to protect our DNA by actually promoting cancer cell death, a process called apoptosis,” she says. Abundant levels of sulfur-containing compounds called glucosinolates, found in cruciferous vegetables such as cauliflower, collard greens, kale, horseradish, bok choy, arugula and cabbage, have also been linked to a decrease in cancer risk.
Abstaining completely from all animal foods may not be necessary to stay cancer-free. “A semi-vegetarian diet that includes fish but not meat also lowers cancer risk,” says Carolyn Lammersfeld, RD, vice president of integrative medicine at Cancer Treatment Centers of America’s Midwestern Regional Medical Center in Chicago. A study published in JAMA (3/15) involving 78,000 people found that avoiding meat and eating a plant-based diet that includes fish may be key in preventing colorectal cancers. In fact, pescetarians (a common term for fish eaters who abstain from meat) had a 43% lower chance of developing cancer compared to those who ate meat. In addition, a study in The Lancet (6/01) showed a decreased risk of prostate cancer among men who consumed fish.
“It’s also extremely important to keep your weight within a healthy range,” notes Lammersfeld. “Fat is like an active organ that raises the risk of cell changes that can contribute to the development of cancer.”
Diet is estimated to play a role in 30% to 70% of all cancers, says Mitch Gaynor, MD, clinical professor of medicine at Weill Cornell Medical College and author of The Gene Therapy Plan (Viking Press). “Nutritional genomics is the study of how the foods you put in your body can literally change the function of thousands of genes in your body including many health issues—and cancer. It’s the new megatrend for both prevention and disease,” explains Gaynor. We all have dormant cancer cells in our bodies, which can develop gene mutations, “and through diet we can control the expression of those genes.”
Certain substances that help promote apoptosis restore the ability of cancer cells to die and keep dormant cells dormant, says Gaynor. He particularly recommends black raspberries (or black raspberry powder), garlic, curry powder (turmeric) and coconut for their ability to encourage apoptosis. “Coconuts are loaded with lauric acid, found only in coconut milk and mother’s milk, that stimulates part of the immune system that suppresses cancer,” Gaynor says.
In fact, researchers are exploring a number of specific foods and nutrients that have been found to possess cancer-fighting properties. (It’s always a good idea to discuss cancer prevention with your healthcare practitioner, who can make suggestions based on your unique risk factors.)
Dial Up the D
According to a 2009 JAMA report, vitamin D levels in the US population have been dropping gradually, a trend that may increase cancer risk. A lack of dietary sources of vitamin D and the use of sunscreen, which blocks the body’s production of the vitamin through the skin, make low levels extremely common. “Vitamin D is a hormone involved in many functions that help reduce the risk of cancer, such as cell differentiation,” says Lammersfeld, who recommends a blood test to determine your specific needs.
Increase Your Omega-3s
Omega-3 fatty acids, especially the eicosapentaenoic acid (EPA) found in fish and krill, may help reduce prostate cancer risk, suggests a Canadian study published in Cancer Prevention Research (7/14). “Walnuts, canola oil and other omega-3 containing foods are anti-inflammatory and are good for the immune system,” says Lammersfeld. The World Health Organization recommends a daily intake of 0.3 to 0.5 grams of EPA along with its partner, DHA (docosahexaenoic acid).
Fixate on Folate
Folate, the B vitamin abundant in dark leafy greens such as kale and spinach as well as asparagus and other foods, plays a role in maintaining DNA and is important for helping the body make new cells, especially red blood cells. Low levels of folic acid in the blood are linked to higher rates of colorectal cancer and other types of cancer. “If you eat enriched grains and a fairly balanced diet you probably get enough,” says Lammersfeld. The current recommended amount (RDA) is 400 micrograms per day for teens and adults.
Toss In Tomatoes
Lycopene, a natural antioxidant found in foods such as tomatoes, pink grapefruit, red grapes, watermelon and papaya, has long been believed to help reduce prostate cancer risk. Now scientists at Wayne State University think it may help lower kidney cancer risk (Cancer 2/15/15). Their study analyzed data from 96,196 women to find those who developed a form of kidney cancer called renal cell carcinoma. Compared with women who reported a lower intake of lycopene, those who ingested more had a 39% lower risk.
Back Off On Alcohol
Although moderate alcohol consumption has been linked to cardiovascular benefits, any level of alcohol intake increases the risk of breast cancer, says Lammersfeld, who notes, “Studies show one drink a day for women increases risk by 9%, but two or more drinks a day jumps it up to 40% increased risk.” Alcohol contains toxins that increase cancers of the gastrointestinal tract and it also appears to raise estrogen levels in women, which is associated with greater breast cancer risk, she explains. Alcohol presents a major risk factor for other cancers as well, including certain head and neck cancers, particularly those of the throat, mouth and larynx (voice box). People who drink 3.5 or more drinks per day have at least two to three times greater risk of developing these cancers than those who abstain, according to the National Cancer Institute. Risk for esophageal, liver and colorectal cancers all increase with alcohol consumption as well.
1. Sauté garlic, onions and bell pepper in small amount of water in a
heated medium-sized saucepan until soft.
2. Add beans, salsa, cumin, chili powder, corn and broth, and mix well.
Bring to boil, then reduce heat and bring to a low simmer for 10 minutes.
3. Ladle soup into bowls and top with shredded cheese and cilantro, if using.
Yield: 8 servings; prep time: 10 minutes; cook time: 30 minutes
REPRINTED WITH PERMISSION OF CAROLYN LAMMERSFELD, RD,
CANCER TREATMENT CENTERS OF AMERICA (CANCERCENTER.COM)
Carolyn Lammersfeld says this soup, which is loaded with cancer-fighting ingredients, can be garnished with a tablespoon of low-fat sour cream and chopped green onion.