Exercising proper nutrition is especially important for cancer patients. Many cancer patients have a decreased appetite and cannot tolerate certain foods. This can result in poorer intake and less nutritional support. In addition, cancer can impair the body's absorption of important nutrients (malabsorption).

According to The National Cancer Institute (NCI), many cancer patients have already experienced weight loss by the time their cancer has been diagnosed. This is particularly true for patients with gastrointestinal cancers and lung cancer. Loss of appetite or a decreased desire to eat is present in 15 to 25 percent of all cancer patients. This may be due to the cancer itself or as a side effect of treatments.

The various cancer treatments can also cause certain side effects that make eating difficult or painful. These side effects include:

• Sore or dry throat and mouth
• Gum or dental problems
• Difficulty swallowing (dysphagia)
• Change in taste or smell
• Nausea or vomiting
• Diarrhea and constipation
• Fatigue
• Depression

The type and severity of side effects depends upon a variety of factors including the type of cancer, the type of treatment, the length of treatment as well as other factors. Patients should speak with their physicians about the eating-related side effects of specific treatments and ways to counteract these problems. For example, if a patient has trouble swallowing, the physician may recommend adding liquids that are thick in consistency, such as milkshakes, or soft foods such as mashed potatoes to the diet.

If the patient often experiences nausea and/or vomiting, the physician may recommend adjusting the meal schedule to include longer periods between eating and treatment sessions, or smaller, more frequent meals. Changing the patient’s diet and antinausea medications also may help reduce these side effects.

The nutritional needs of people with cancer vary from patient to patient, and depend on factors such as the patient’s size and age, and whether an individual has experienced significant weight loss (5 percent of total body weight or more) due to treatment. Patients should discuss their nutritional goals with their physician and/or dietitian. Eating well during cancer therapy can help patients:

• Feel better
• Maintain their strength and energy
• Maintain their body weight
• Maintain their body’s store of essential nutrients
• Tolerate treatment and its side effects
• Decrease their risk of infection

Proper nutrition may also speed up the healing and recovery time of some patients. Eating well may even help some individuals handle higher doses of certain cancer treatments. In addition, cancer patients who are well-nourished typically have a better prognosis (predicted outcome for survival).

For cancer patients, eating well means consuming a variety of foods that provide the nutrients needed to help maintain their health while battling cancer. These essential nutrients include:

• Protein. Protein helps to repair body tissue, maintain the immune system’s health and ensure growth. With insufficient protein, the body’s resistance to infection is reduced and recovery from illness may take longer. Therefore, cancer patients may require more protein than those without cancer. After surgery, radiation therapy or chemotherapy, extra protein is typically needed to mend tissues and help prevent infection. Good sources of protein include:
  
  
• • Lean meat and poultry
  • Fish
  • Low-fat dairy products
  • Nuts
  • Dried beans, lentils and peas
  • Soy foods
  • Egg whites
    
    
• Carbohydrates and fats. These nutrients supply the body with the majority of its caloric needs. The amount of calories a person needs depends on size, age and level of physical activity. Sources of carbohydrates include:
  
  
• • Fruits
  • Vegetables
  • Pasta and breads
  • Grains and cereals
  • Dried beans, lentils and peas
    
    
  Sources of fat include:
  
  
  • Seeds and nuts
  • Butter, margarine and oils
  • Cheeses and other fatty dairy products
  • The fat in poultry, fish and meats
  • Egg yolks

The U.S. Department of Agriculture’s (USDA) revised food pyramid (now known as My Pyramid) suggests limiting consumption of fats and oils. In addition, fish oils and some vegetable oils, such as olive oil, have health benefits. The USDA recommends avoiding artery-clogging trans fats (such as partially hydrogenated vegetable shortening), saturated fats and cholesterol.

• Vitamins and minerals. These nutrients are the basics for proper growth and development. They also enable the body to use the energy (calories) supplied in foods. Individuals who eat a balanced diet with sufficient calories and protein typically get enough vitamins and minerals. However, some side effects of cancer treatment can make eating a balanced diet very challenging. Therefore, physicians may recommend that patients who are undergoing cancer treatment take a daily multivitamin and mineral supplement.
  
  
• Water. Water and other fluids are essential to good health. Individuals who do not consume enough water, or lose water due to vomiting or diarrhea, can become dehydrated. Patients should ask their physician or dietitian how many ounces of water they should consume daily.

In general, cancer patients should strive to consume the following each day:

• Six servings of grains, preferably whole (unrefined)
• Three to five servings of vegetables
• Two to four servings of fruit
• Eight 8-ounce glasses of water

Many cancer patients seek nutritional support prior to beginning cancer treatment. Early nutrition screening and assessment can help to identify any problems that may impact the success of cancer therapy. Early discovery and treatment of nutrition problems may help a patient maintain a healthy weight and reduce some of the complications from treatment. Patients who are otherwise healthy typically respond better to cancer therapy.

The patient’s cancer care team can play a vital role in maintaining adequate nutrition. The team usually includes a medical oncologist, oncology nurses and a social worker. Depending on the type of cancer, it may include a radiation oncologist, surgeon, psychologist and dietitian. Working together, the team can help the patient maintain the best nutritional status as possible.

Cancer patients who are unable to eat well because of treatment-related side effects may benefit from nutritional therapy. Nutritional therapy is designed to help patients in active treatment and recovery as well as those with advanced cancer. Goals of nutritional therapy may include preventing/correcting malnutrition, decreasing nutrition-related side effects, improving the patient’s quality of life. Nutritional therapy varies according to patient and treatment type, but may include:

• A specialized diet plan
• Nutritional supplement beverages
• Enteral nutrition (a short-term feeding tube inserted through the nose, down the throat and into the stomach, or a long-term tube surgically placed through the abdomen into the stomach or small intestine)
• Parenteral nutrition (an intravenous feeding tube)
• Appetite-improving medications