Maintaining a healthy diet plays a critical role in preventing cancer. While everyone should develop eating habits that will reduce the risk of cancer later in life, it is particularly important for cancer survivors. Healthy eating habits can help reduce the risk of obesity and may reduce the risk of some types of adult cancers.
Recommendations for diet, weight, and physical activity include:
- Eat more plant-based foods such as grains, vegetables, fruit and beans.
- Eat less red meat, and avoid processed meat.
- Avoid high-calorie foods and sugary drinks.
- Avoid preservatives, and eat less salt.
- Limit intake of alcohol.
- Keep weight within a healthy range.
- Be physically active on a regular basis.
Nutrition professionals recommend eating a healthy diet, with a special emphasis on fruits, vegetables, and whole grains. In addition, controlling calorie intake can help in maintaining a healthy weight.
- Refined carbohydrates. Pastries, candy, sweetened breakfast cereals, cookies, and other sweet foods can contain high amounts of sugars.
- Dietary fat. Several types of adult cancers have been linked to a high intake of saturated fats and trans fats found in beef and pork, butter, shortening and margarine. High-fat diets may increase the risk of colon, breast, and prostate cancers and are associated with obesity, heart disease, and other health problems. Saturated fat should be limited to no more than 10% of total daily calories.
- Processed meat and red meat. Limit foods like bacon, sausage, lunch meats, and hot dogs. When eating red meat, choose lean cuts. Bake, broil, or poach instead of frying or charbroiling. Consider healthier alternatives such as fish, poultry, or beans.
- Preservatives. Some foods, such as salt-cured and pickled foods and lunchmeats, contain preservatives like nitrites, which are chemicals used to preserve foods. These foods can increase the risk of cancer in the stomach and esophagus when eaten in large quantities.
Pay close attention to portion size and calories.
- Read food labels for portion sizes and calories.
- Choose low calorie foods like vegetables and whole fruits.
- Eat smaller portions of high-calorie foods such as french fries, potato and other chips, ice cream, donuts, and other sweets.
- Limit sugary beverages such as sweetened soft drinks, sports drinks, and fruit-flavored drinks.
Foods that May Protect Against Cancer
Researchers have studied how certain types of food and parts of foods could affect cancer growth. There is evidence that certain substances in foods might slow cancer cell growth and protect against cancer:
- Plant-based foods have naturally-occurring chemicals that might have an anticancer effect. These include:
- Phytochemicals, found in red, orange, yellow, and some dark-green vegetables
- Polyphenols, found in herbs, spices, vegetables, green tea, apples, and berries
- Allium compounds, found in chives, garlic, leeks, and onions
- Glucosinolates, found in cruciferous vegetables such as cabbage, Brussels sprouts, broccoli, and cauliflower
- Antioxidants, such as beta carotene, lycopene, and vitamins A, C, and E can reduce the risk of cell damage.
- Dietary fiber helps food move more quickly through the digestive system.
- Whole grains and seeds, such as barley, oats, bulgur, corn, and rye
- Whole grain bread and pasta
- Legumes and pulses like black beans, garbanzo beans, lentils, and split peas
- Vegetables and fruits
Eating more calories than the body needs can result in weight gain.
Being overweight or obese is linked with an increased risk of several types of cancer including:
- Breast (particularly in women who have gone through menopause)
- Colon and rectum
- Endometrium (lining of the uterus)
Alcohol and Cancer Risk
Drinking alcohol, such as wine, beer and liquor, increases the risk of cancer. Alcohol is directly linked to the risk of developing cancers of the head and neck, liver, esophagus, breast cancer and colon and rectum.
While researchers do not know exactly why alcohol increases cancer risk, possibilities include:
- Alcohol has chemicals that can damage DNA and proteins of healthy cells.
- Alcohol may increase the amount of estrogen in the blood and increase the risk of breast, ovarian, and uterine cancers.
- Alcohol may reduce the body’s ability to process and absorb important nutrients, including Vitamins, A, C, D, and E, as well as folate and carotenoids
If adults drink alcohol, intake should be limited to up to 2 drinks per day for men and up to 1 drink per day for women. A drink is defined as 12 ounces of beer, 5 ounces of wine and 1.5 ounces of 80-proof liquor (distilled alcohol).
Other suggestions to limit alcohol use include:
- Do not binge drink or drink heavily.
- Do not make an exception for red wine.
- Do not use alcohol in combination with tobacco products, as it further increases the risks of developing certain cancers.
Talk with a provider about the risk for the cancer. Doctors may recommend limiting or avoiding alcohol entirely to help reduce the risk for secondary cancer.
It is also important for patients to ask a doctor if it is safe to drink alcohol during illness or while taking certain drugs.