In 2018, an estimated 1,735,350 new cases of cancer will be diagnosed in the United States, with the most common cancers being breast cancer, lung cancer, prostate cancer and colorectal cancer. The good news is more and more patients are surviving cancer. For example, in 2016, there were an estimated 15.5 million cancer survivors in the U.S.
Good nutrition is key, both during and after cancer treatment. Nutrition is the process by which food is taken in and used by the body for growth, to keep the body healthy and to replace tissues. A healthy diet involves eating and drinking enough foods and liquids that have the nutrients your body needs. These nutrients include vitamins, minerals, protein, carbohydrates, fat and water.
While cancer treatments can take a toll on your body, eating the right foods can help you feel better and rally faster. Eating well can also help you tolerate treatment-related side effects and add to your strength and energy.
Understanding the Importance of Proteins, Fats, Carbs, and Water
Each cancer patient is different, but there are some general nutrition concepts to keep in mind. For example, people undergoing cancer treatment often need more protein. This is because protein is vital to healing tissues and to helping keep the immune system healthy. If you don't have enough protein during cancer treatment, your body may break down muscle tissue instead for the fuel it needs. If this happens, it may take you longer to recover from treatment and make you more at risk to infections.
Fats are a main source of energy for the body. Specifically, fats help you store energy, insulate body tissues and carry certain vitamins throughout the blood. For example, ‘fat-soluble vitamins' are absorbed along with fats in the diet and can be stored in the body's fatty tissue. Vitamins A, D, E, and K are examples of fat-soluble vitamins. In general, it's better to have monounsaturated and polyunsaturated fats, which come from vegetable oils, than saturated or trans fats. Saturated fats are most often found in meat products. Trans fats are often found in baked goods or fried foods.
Carbohydrates are the body's major source of energy and gives your body with the fuel it needs for physical activity and proper organ function. Fruits, vegetables and whole grains are ideal sources of carbohydrates. When possible, choose these foods over more processed forms of carbohydrates like sweet or sugary foods, which have limited nutritional value.
Water and other liquids are also critical for helping you stay hydrated and with overall healing. All body cells need water to function. It's especially important to increase your fluid intake if you're experiencing vomiting or diarrhea because of your cancer treatment. Remember, all liquids count toward your fluid intake -- even soups, milk and tea.
How Cancer Itself and Related Treatments Affect Nutrition
When the head, neck, esophagus, stomach or liver are affected by the cancer treatment, it can be hard to take in enough nutrients to stay healthy. Some cancer treatments may also affect your taste, smell, appetite and the ability to eat enough food or absorb the nutrients from food. This can cause malnutrition, which is a health issue caused by a lack of key nutrients. Malnutrition may cause patients to be weak, tired and not able to fight an infection or finish cancer treatment. The issue of malnutrition may be worse if the cancer grows or spreads. By working with your cancer care team and a registered dietitian, you can help ensure you are eating the right amount of protein and calories.
What's a Registered Dietitian and How Can I Find One
A registered dietitian (or nutritionist) is a part of the team of health experts that help with cancer treatment and recovery. A dietitian will work with patients, their families and the rest of the health care team to manage the patient's diet during and after cancer treatment. For many patients, the effects of cancer and cancer treatments make it hard to eat well. In these cases, ‘nutrition therapy' is used to help cancer patients keep a healthy body weight, maintain strength and keep body tissue healthy both during and after treatment.
Many cancer centers have registered dietitians on staff. Some cancer centers even offer nutrition classes. If your health center does not offer such services, you can search for a registered dietitian through your health insurance company or other professional firms like the Academy of Nutrition and Dietetics.
Special Considerations for Prostate, Kidney, and Bladder Cancers
"To date, there hasn't been good evidence to show that a specific diet or certain foods will help prostate cancer patients heal more quickly during cancer treatment," says J. Kellogg Parsons, MD, a board-certified urologist at UC San Diego Health's Moores Cancer Center who specializes in diagnosing and treating prostate cancer.
There is also limited evidence about any unique eating patterns needed for kidney or bladder cancer patients. We do know, however, that one of the best things you can is to quit smoking during treatment. Smoking has been shown to reduce the effectiveness of many cancer treatments.
"It's still a good idea to follow a general healthy eating plan during treatment," says Parsons. That's because when cancer patients eat well, they often feel stronger. And this can help them better deal with the physical and emotional stresses related to cancer treatment.
Dr. Parsons also notes that what's generally good for the heart is also generally good for cancer. This includes eating a diet rich in fruits, vegetables and whole grains. And watching your fat, sugar and salt intake.
Maintaining Good Nutrition After Cancer Treatments
Even after cancer treatment ends, some cancer patients will have eating-related side effects such as weight changes or dry mouth. Other cancer patients may have trouble swallowing food, post-treatment. This is common among head and neck cancer patients. If you experience any of these problems, talk to your cancer care team right way. They will work with you to develop a plan of action that's right for you.
General tips for eating well after cancer include:
- Make meals fun! Think of ways to make a colorful plate with different fruits and vegetables.
- Eat balanced meals that include all the food groups.
- Don't skip meals.
- Eat high-fiber foods like whole-grain breads and legumes.
- Avoid added sugars and processed foods as much as possible.
- Limit your intake of red meat (beef, pork, or lamb) to no more than 3 to 4 servings a week.
You may also consider working with a registered dietitian or finding a good cookbook to create healthier versions of the foods you like. For example, instead of frying chicken in vegetable oil you can make "oven fried chicken" with less fat, calories and salt. Finally, if you decide to drink alcohol, limit the amount to no more than 1 drink per day for women, and 2 for men.
By eating well, you'll be on your way to feeling better both during and after cancer treatment.