Fight cancer with your fork; it’s an idea that encourages us to choose a healthy diet and avoid foods that pack on pounds and prime the body for cancer and other chronic diseases.
Being on board with that approach isn’t a stretch. Figuring out what to eat, however, can feel a little overwhelming. That’s partly because we can’t say for sure that certain foods stop or prevent cancer, thanks to the nature of scientific studies. “Diet studies in general are really hard to do. They typically fall into the category of having people remember what they ate over time and then making correlations ,” says Dr. Dale Shepard, an oncologist at Cleveland Clinic.
But some relationships between diet and health have been proved consistently.
Certain foods and drinks have been shown to have a strong association with cancer. They include:
— Red meat, such as beef, pork or lamb. Red meat has high levels of iron that may contribute to cancer growth, and in particular colorectal cancer (cancer of the colon or the rectum). Red meat’s cancer association may also have something to do with the way meat is cooked. “Heterocyclic amines and polycyclic aromatic hydrocarbons are formed when meat is exposed to high temperatures during the cooking process, especially when grilling, and have been linked to colorectal cancer,” says Rebecca Hively, a clinical dietitian nutritionist at Moffitt Cancer Center.
— Processed meats, such as bacon, ham or hot dogs. “In this case, the link may have something to do with the way meat is processed,” Shepard says. “Often, it contains nitrates and nitrites, which can damage cells at the DNA level that causes them to grow in an abnormal way.”
— Alcohol. “Drinking alcohol can raise one’s risk for cancer of the mouth, throat, larynx, esophagus, liver, breast, colon, rectum, pancreas and stomach. The more alcohol you drink, the higher the risk,” notes Katrina Hartog, director of clinical nutrition at Mount Sinai Health System.
Indirect Cancer Links
A generally unhealthy diet can also affect your cancer risk. Consuming lots of processed, fatty, sugary or high-calorie foods or drinks can lead to two conditions that play a role in cancer development.
— Overweight or obesity. “One of the main ways excess weight increases cancer risk is the impact on the body to make and circulate more estrogen and insulin; both are hormones that can stimulate cancer growth,” Hartog says. Obesity is associated with cancers of the breast, colon, rectum, endometrium, esophagus, pancreas, liver and kidney. “It’s estimated that as many as 10% of cancers in women and 5% in men are related to obesity,” Shepard says.
— Chronic inflammation. Both obesity and an unhealthy diet promote chronic inflammation. “The inflammatory process begins when chemicals are released by damaged tissues, which then triggers white blood cells to make substances that cause cells to divide and grow. This is the tissue repair and growth process. Usually the process stops there, but with chronic inflammation the process doesn’t end when it should,” Hively explains. “Over time, chronic inflammation in the body can lead to DNA damage, which may lead to cancer.”
To stave off cancer with diet, the American Institute for Cancer Research recommends a plant-focused eating pattern, with plant foods such as vegetables, legumes and grains filling about two-thirds of your plate. The diet can also include moderate amounts of animal-based foods, as long as they’re no more than a third of each meal.
Several diets fit the bill, including:
— A vegetarian diet (with or without dairy foods or fish).
— A Mediterranean-style diet (which includes poultry and fish).
What those diets have in common:
— Whole, unprocessed vegetables and fruits (the more colorful, the better).
— Whole grains (not refined, like white bread).
— Legumes (such as beans or lentils).
— Seeds and nuts.
— Lean proteins (such as fish).
— Plant-based oils (like olive or canola oil).
How they help in the fight against cancer development:
— They’re loaded with vitamins, minerals and phytochemicals (plant chemicals like flavonoids) that work together to reduce chronic inflammation and have an anti-cancer effect.
— Plant foods are rich in fiber. “Fiber helps with the transit of food in the GI tract,” Shepard says. “Food that sits in the GI tract longer than it should affects the type of bacteria and inflammation in the gut.”
[See: The Best Plant-Based Diets.]
Making It Work
Switch to a healthier diet gradually, so it won’t feel restrictive and you’ll have a better chance at sustaining the eating pattern. A food diary may be helpful to track what you’re eating and how your diet is improving.
Don’t feel you can’t cheat now and then. “It’s not like eating a piece of bacon will give you cancer. But don’t make it a major component or base of your food pyramid,” Shepard says. “Moderation in everything is reasonable.”
Other tips that can help:
— Start buying healthier foods. Keep fresh produce, beans, nuts, seeds and whole grains on hand so you’ll have real (not processed) foods available when you’re hungry.
— Pay attention to food labels. “Avoid or limit foods with high levels of added sugars,” Hartog advises.
— Use healthier cooking methods. “Prepare foods by baking, broiling or poaching rather than frying or charbroiling,” Hartog recommends.
— Stay hydrated. “Consume water rather than sweetened beverages,” Hively recommends.
— Avoid or limit alcohol consumption. The guidelines advise no more than one drink per day for women and no more than two drinks per day for men.
Beyond Anti-Cancer Foods
It takes more than a healthy diet to try to avoid cancer. You also need to live a healthy lifestyle that includes weight control. “It’s not just fighting cancer with your fork; it’s not using your fork too often, so you’ll fight obesity,” Shepard points out.
Other important components of a healthy lifestyle include:
— Daily exercise. Aim for 30 minutes per day or get at least 120 minutes of moderate intensity exercise (like brisk walking) per week.
— Adequate sleep. Try to get seven or eight hours per night.
— Stress reduction. Chronic stress triggers chronic inflammation. Meditation, deep breathing exercises or yoga can help reduce stress.
— Stop smoking. Smoking is directly related to many kinds of cancer.
All aspects of a healthy lifestyle work together and give you a better chance at warding off cancer. “There is no one thing,” Shepard says. “It’s all about balance.”
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