The best surgery, chemotherapy and radiation therapy are not always enough to prevent a cancer recurrence. In an estimated four out of every 10 cancer cases, the malignancy comes back despite state-of-the-art medicine.
To maximize the effectiveness of standard cancer treatment, you need an integrative program that includes a healthful diet, emotional support and regular exercise. This type of approach may give the 9.8 million Americans who are cancer survivors the best possible chance of avoiding a recurrence—and help protect people who have never had cancer and want to do all they can to prevent it.
Conventional oncologists usually advise patients to avoid weight loss, a significant side effect of chemotherapy and radiation. But for most people with cancer, avoiding weight gain is just as important. Research shows that excess weight increases the risk for the development and recurrence of many cancers as well as associated mortality.
What's the link between weight and cancer? Insulin resistance is one theory that is being extensively studied. Insulin, a hormone produced by the pancreas, is vital for glucose (blood sugar) metabolism-it brings this simple sugar into the cells to be broken down for energy. Trouble develops when the cells become less sensitive to insulin, usually as a result of a person being overweight and/or underactive. The pancreas responds by producing more insulin, and higher levels of the hormone remain in the bloodstream.
Excessive insulin levels have been linked to persistent, low-grade inflammation, which releases chemicals that stimulate the growth of cells. Many experts believe that inflammation also stimulates the growth of cancer cells. Cancer and some cancer treatments, such as hormone therapy, may increase insulin resistance as a result of decreased metabolism, reduced activity levels and changes in nutritional intake.
People diagnosed with cancer, especially if they are overweight, should be tested for insulin resistance by checking levels of fasting blood sugar, insulin and lipids, and seek treatment with medication if necessary.
A Cancer-Fighting Diet
Weight control is one of the most important ways to help your body fight cancer and promote recovery. Unfortunately, many cancer patients seek fattening comfort food, or their doctors tell them to eat whatever they want.
The ideal cancer-fighting diet consists of 45% complex carbohydrates, 25% protein and no more than 30% fat. Strong evidence has shown that this kind of balanced diet is associated with lower rates of cancer and cancer recurrence.
The Mediterranean diet-including ample amounts of fruits and vegetables, whole-grain cereals and olive oil-is a wise choice. Small meals eaten four to six times a day also are recommended. That's because people who consume their food over the course of the day—rather than in one to three big meals—tend to take in fewer calories and stay healthier.
The same guidelines are important if your appetite is diminished by nausea caused by chemotherapy or the cancer itself. In these cases, a balanced diet is important because it helps prevent nutritional deficiencies that can result from appetite loss.
To create a cancer-fighting diet…
- Choose the right carbs. The amount of carbohydrates you consume isn't as critical as the kind. Sharply limit pastries, candies, beverages containing high-fructose corn syrup, such as soft drinks and some fruit juice drinks, and refined grain products, such as white rice and bread made from white flour. The carbohydrates in these foods are broken down immediately and deposited into the bloodstream, triggering an insulin surge. With repeated exposure to insulin peaks, cells become less sensitive to the hormone.
Complex carbohydrates, such as fruits and vegetables, beans, brown rice, whole-grain cereals and whole-grain baked goods, are digested and absorbed gradually. Insulin is produced at a steady, moderate rate, fueling the body's cells with maximum efficiency. What's more, the fiber in complex carbs fills you up, so you can satisfy your hunger with fewer calories.
Eat a variety of vegetables and fruits. Specific "superfoods, such as beans and blueberries, have received a great deal of attention for their healing properties, but it's crucial to get a broad selection of healthful foods.
Fruits and vegetables should be a mainstay of your diet—the American Cancer Society recommends at least five daily servings. Nine daily servings are even better. One-half cup is the standard serving size. In addition to fiber and complex carbohydrates, fruits and vegetables contain chemicals known as phytonutrients that protect against carcinogens and enhance the body's own healing powers.
Broccoli, cauliflower and cabbage have different phytonutrients than garlic and onion. Berries, citrus fruits and leafy, green vegetables each have their own nutrients. Eating a variety of fruits and vegetables ensures that you get them all.
- Avoid dangerous fats. Saturated fats, found mostly in meats and high-fat dairy products, promote insulin resistance, so limit your meat intake to two servings (three ounces per serving) of lean red meat per week and consume only low-fat or nonfat dairy products (one to three servings daily). Good protein sources include poultry, fish, nuts and legumes.
Trans fat, found in many baked goods and processed foods, also causes inflammation.
Beware: Even in food products that claim "0" trans fat on the food labels, small amounts may be present and listed as "partially hydrogenated oil."
On the other hand, omega-3 fatty acids, found in cold-water fish, such as salmon, sardines and herring, have been shown to reduce inflammation and provide a range of other anticancer benefits. Other sources of omega-3s include walnuts and flaxseed.
Important: Food is the best way to get vitamins, minerals and other nutrients. High-dose supplements should be taken only under the supervision of a health-care professional who is knowledgeable about nutrition and cancer care.
Be Sure To Find Emotional Support
Serious illness, such as cancer, can trigger the release of stress hormones that increase your risk of developing excessive insulin levels.
- Get emotional support. In a Yale study that followed more than 300 women with breast cancer for 10 years, those who felt free to talk about their illness with others were significantly more likely to survive. Don't be reluctant to ask friends and family for help in performing difficult chores and for company during doctor visits.
- Choose a doctor who gives you hope. Hopelessness and helplessness are the worst stressors for people with cancer. Make sure your care is directed by a medical professional who focuses on the most positive possible outcome, even if the disease is severe.
Exercise Is Essential
Exercise reduces insulin resistance by building up lean, metabolically active tissue—which is better than fat tissue for cancer prevention.
In a recent study of 2,987 breast cancer patients, women who walked three to four hours a week had a 50% lower risk of dying from breast cancer than women who did little or no exercise. Researchers believe that physical activity also helps fight other types of malignancies.
For cancer prevention, strive for 30 minutes of brisk walking per day—or its equivalent in comparably strenuous activities, such as swimming or cycling