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Nutrition for Persons with Cancer

From "National Cancer Institute", for further details, please contact the website.

Overview of Nutrition in Cancer Care

Cancer and cancer treatments may cause nutrition-related side effects.

The diet is an important part of cancer treatment. Eating the right kinds of foods before, during, and after treatment can help the patient feel better and stay stronger. To ensure proper nutrition, a person has to eat and drink enough of the foods that contain key nutrients (vitamins, minerals, protein, carbohydrates, fat, and water). For many patients, however, some side effects of cancer and cancer treatments make it difficult to eat well. Appetite, taste, and the ability to eat enough food or absorb the nutrients from food may be affected. Malnutrition (lack of key nutrients) can result, causing the patient to be weak, tired, and unable to resist infections or withstand cancer therapies. Eating too little protein and calories is the most common nutrition problem facing many cancer patients. Protein and calories are important for healing, fighting infection, and providing energy.

Anorexia and cachexia are common causes of malnutrition in cancer patients.

Anorexia (the loss of appetite or desire to eat) is a common symptom in people with cancer. Anorexia may occur early in the disease or later, when the tumor grows and spreads. Some patients may have anorexia when they are diagnosed with cancer. Almost all patients who have widespread cancer will develop anorexia. Anorexia is the most common cause of malnutrition in cancer patients.

Cachexia is a wasting syndrome that causes weakness and a loss of weight, fat, and muscle. Anorexia and cachexia often occur together. Cachexia can occur in people who are eating enough, but who cannot absorb the nutrients. Cachexia is not related to the tumor size, type, or extent. Cancer cachexia is not the same as starvation. A healthy person's body can adjust to starvation by slowing down its use of nutrients, but in cancer patients, the body does not make this adjustment.

Good eating habits during cancer care help the patient cope with the effects of the cancer and its treatment.

Nutrition therapy can help cancer patients get the nutrients needed to maintain body weight and strength, prevent body tissue from breaking down, rebuild tissue, and fight infection. Eating guidelines for cancer patients can be very different from the usual suggestions for healthful eating. Nutrition recommendations for cancer patients are designed to help the patient cope with the effects of the cancer and its treatment. Some cancer treatments are more effective if the patient is well nourished and getting enough calories and protein in the diet. People who eat well during cancer treatment may even be able to handle higher doses of certain treatments.

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Effect of Cancer on Nutrition

Tumors may produce chemicals that change the way the body uses certain nutrients. The body's use of protein, carbohydrates, and fat may be affected, especially by tumors of the stomach or intestines. A patient may appear to be eating enough, but the body may not be able to absorb all the nutrients from the food. Diets higher in protein and calories can help correct this and prevent the onset of cachexia. It is important to monitor nutrition early, as cachexia is difficult to completely reverse.

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Effect of Cancer Treatment on Nutrition

Effect of Surgery on Nutrition

Surgery increases the body's need for nutrients and energy.

The body needs extra energy and nutrients to heal wounds, fight infection, and recover from surgery. If the patient is malnourished before surgery, there may be complications during recovery, such as poor healing or infection. Patients with certain cancers, such as cancers of the head, neck, stomach, and intestines, may be malnourished at diagnosis. Nutrition care may therefore begin before surgery.

Nutrition-related side effects may occur as a result of surgery.

More than half of cancer patients have cancer-related surgery. Surgery may include the removal of all or parts of certain organs, which may affect a patient's ability to eat and digest food. The following are nutrition problems related to specific surgeries:

• Surgery to the head and neck may cause chewing and swallowing problems. Mental stress due to the amount of tissue removed during surgery may affect appetite.
• Surgery involving cancer of organs in the digestive system may lessen the ability of the digestive system to work properly and may slow the digestion of food. Removal of part of the stomach may cause a feeling of fullness before enough food has been eaten. Stomach surgery may also cause dumping syndrome (emptying of the stomach into the intestines before food is digested). Some of the organs in the digestive system normally produce important hormones and chemicals that are necessary for digestion. If surgery affects these organs, the protein, fat, vitamins, and minerals in the diet may not be absorbed normally by the body. Levels of sugar, salt, and fluid in the body may become unbalanced.

Nutrition therapy can treat these problems and help cancer patients get the nutrients they need.

Nutrition therapy can treat the nutrition-related side effects of surgery.

Nutrition therapy may include the following:

• Nutritional supplement drinks
• Enteral nutrition (feeding liquid through a tube into the stomach or intestine)
• Parenteral nutrition (feeding through a catheter into the bloodstream)
• Medications to improve the appetite.

Surgery may cause fatigue, pain, and loss of appetite.

It is common for patients to experience pain, tiredness, and/or loss of appetite after surgery. For a short time, some patients may not be able to eat their regular diet because of these symptoms. The following eating tips may help:

• Avoid carbonated drinks (such as sodas) and gas-producing foods (such as beans, peas, broccoli, cabbage, brussel sprouts, green peppers, radishes, and cucumbers).
• If regularity is a problem, increase fiber by small amounts and drink lots of water. Good sources of fiber include whole-grain cereals (such as oatmeal and bran), beans, vegetables, fruit, and whole grain breads.
• Choose high-protein and high-calorie foods to help wounds heal. Good choices include eggs, cheese, whole milk, ice cream, nuts, peanut butter, meat, poultry, and fish. Increase calories by frying foods and using gravies, mayonnaise, and salad dressings. Supplements high in calories and protein are available.

Effect of Chemotherapy on Nutrition

Chemotherapy may affect the whole body.

Chemotherapy is a cancer treatment that uses drugs to stop the growth of cancer cells, either by killing the cells or by stopping the cells from dividing. Because chemotherapy targets rapidly dividing cells, healthy cells that normally grow and divide rapidly may also be affected by the cancer treatments. These include cells in the mouth and digestive tract.

Nutrition-related side effects may occur during chemotherapy.

Side effects that interfere with eating and digestion may occur during chemotherapy. The following side effects are common:

• Anorexia
• Nausea
• Vomiting
• Diarrhea or constipation
• Inflammation and sores in the mouth
• Changes in the way food tastes
• Infections

Nutrition therapy can treat the nutrition-related side effects of chemotherapy.

The side effects of chemotherapy may make it difficult for a patient to obtain the nutrients needed to regain healthy blood counts between chemotherapy treatments. Nutrition therapy can treat these side effects and help chemotherapy patients get the nutrients they need to tolerate and recover from treatment, prevent weight loss, and maintain general health. Nutrition therapy may include the following:

• Supplements high in calories and protein
• Enteral nutrition (tube feedings)

Effect of Radiation Therapy on Nutrition

Radiation therapy can affect healthy cells in the treatment area.

Radiation therapy is a cancer treatment that uses high energy x-rays or other types of radiation to kill cancer cells. There are two types of radiation therapy. External radiation therapy uses a machine outside the body to send radiation toward the cancer. Internal radiation therapy uses a radioactive substance sealed in needles, seeds, wires, or catheters that are placed directly into or near the cancer.

Healthy cells that are near the cancer may be affected by the radiation treatments, and side effects may occur. The side effects depend mostly on the radiation dose and the part of the body that is treated.

Nutrition-related side effects may occur during radiation therapy.

Radiation therapy to any part of the digestive system is likely to cause nutrition-related side effects. The following side effects may occur:

• Radiation therapy to the head and neck may cause anorexia, taste changes, dry mouth, inflammation of the mouth and gums, swallowing problems, jaw spasms, cavities, or infection.
• Radiation therapy to the chest may cause infection in the esophagus, swallowing problems, esophageal reflux (a backwards flow of the stomach contents into the esophagus), nausea, or vomiting.
• Radiation therapy to the abdomen or pelvis may cause diarrhea, nausea and vomiting, inflammation of the intestine or rectum, and fistula (holes) in the stomach or intestines. Long-term effects can include narrowing of the intestine, chronic inflamed intestines, poor absorption, or blockage in the stomach or intestine.
• Radiation therapy may also cause tiredness, which can lead to a decrease in appetite and a reduced desire to eat.

Nutrition therapy can treat the nutrition-related side effects of radiation therapy.

Nutrition therapy during radiation treatment can provide the patient with enough protein and calories to tolerate the treatment, prevent weight loss, and maintain general health. Nutrition therapy may include the following:

• Nutritional supplement drinks between meals
• Enteral nutrition (tube feedings)
• Other changes in the diet, such as eating small meals throughout the day and choosing certain kinds of foods

Effect of Immunotherapy on Nutrition

Nutrition-related side effects may occur during immunotherapy.

Immunotherapy is treatment that uses the patient's immune system to fight cancer. Substances made by the body or made in a laboratory are used to boost, direct, or restore the body's natural defenses against cancer. This type of cancer treatment is also called biologic therapy or biotherapy.

The following nutrition-related side effects are common during immunotherapy:

• Fever
• Nausea
• Vomiting
• Diarrhea
• Anorexia
• Tiredness

Nutrition therapy can treat the nutrition-related side effects of immunotherapy.

If the side effects of immunotherapy are not treated, weight loss and malnutrition may occur. These conditions can cause complications during recovery, such as poor healing or infection. Nutrition therapy can treat side effects from immunotherapy and help patients get the nutrients they need to tolerate treatment, prevent weight loss, and maintain general health.

Effect of Bone Marrow and Stem Cell Transplantation on Nutrition

Bone marrow and stem cell transplant patients have special nutritional needs.

Bone marrow and stem cell transplantation are methods of replacing blood-forming cells destroyed by cancer treatment with high doses of chemotherapy or radiation therapy. Stem cells (immature blood cells) are removed from the bone marrow of the patient or a donor and are frozen for storage. After the chemotherapy and radiation therapy are completed, the stored stem cells are thawed and given back to the patient through an infusion. Over a short time, these reinfused stem cells grow into (and restore) the body's blood cells.

Chemotherapy, radiation therapy, and medications used in the transplant process may cause side effects that prevent a patient from eating and digesting food as usual. These side effects include the following:

• Taste changes
• Dry mouth
• Thick saliva
• Mouth and throat sores
• Nausea and vomiting
• Diarrhea
• Constipation
• Lack of appetite
• Weight gain

Transplant patients also have a very high risk of infection. The high doses of chemotherapy and radiation therapy reduce the number of white blood cells, the cells that fight infection. Cancer patients should be especially careful to avoid infections and food-borne illnesses. Patients are advised to avoid eating certain foods that may carry harmful bacteria.

Nutrition therapy can treat the nutrition-related side effects of bone marrow and stem cell transplantation.

Patients undergoing the transplant process need adequate protein and calories to tolerate and recover from the treatment, prevent weight loss, fight infection, and maintain general health. Nutrition therapy is also designed to avoid possible infection from bacteria in food. Nutrition therapy during the transplant process may include the following:

• A diet of only cooked and processed foods, avoiding raw vegetables and fresh fruit.
• Instruction on safe food handling.
• Specific diet guidelines based on the type of transplant and the cancer site.
• Parenteral nutrition (feeding through the bloodstream) during the first few weeks after the transplant is complete, to ensure the patient gets the calories, protein, vitamins, minerals and fluids needed for good health.

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