Anorexia is characterized by a loss of appetite or lack of desire to eat.
Anorexia is common in cancer patients with reported incidence between 15% and 40%. Primary anorexia is especially prevalent in patients with advanced malignancy, and is frequently a side effect of cancer treatments. Sometimes, early symptoms may remain undiagnosed, or will be masked by a more generalized wasting of the body from chronic disease, known as cachexia.
When patients experience appetite loss, decreased energy consumption will subsequently lead to weight loss. When inadequate calories are consumed, the body may become weaker and less able to tolerate cancer therapies. As body weight decreases, cachexia sets in, and a general failure to thrive may make it more difficult to fight off illness and infection. A poor response to cancer treatments, reduced quality of life, and death may result from substantial weight loss. The spiraling effect of a patient's reluctance to eat is a source of frequent anxiety for caregivers. Weight loss due to anorexia may be temporary or may continue at a life-threatening pace if the patient continues to consume inadequate energy to sustain bodyweight.
It is normal for a patient to consume less energy when not as active. It is also natural to lose interest in food when individuals are seriously ill. However, it is essential in anorexic patients to consider whether the loss of appetite is the result of a natural disinterest in eating (primary anorexia), or is due to some reversible cause (secondary anorexia).
Secondary anorexia may be a result of:
- nausea with or without fear of vomiting after food consumption
- sores in the mouth or mouth pain
- unappetizing food or change in food preference due to cancer-related treatments
- odors in the environment, or heightened sensitivity to odors as a result of cancer-related treatments
- early satiation
- metabolic causes such as hypercalcemia and uremia
- radiation therapy or chemotherapy
- drugs such as antibiotics or drugs that can cause nausea
In order to allow normal tissue repair following aggressive cancer therapies, patients require adequate energy and macronutrients in the form of protein, carbohydrates, and fat. Inadequate consumption of food and/or poor nutrition may impair the ability of a patient to tolerate a specific therapy. If a low tolerance to therapy necessitates a decrease in dose, the therapy's effectiveness could be compromised. Wound healing may also be impaired with poor nutrition and inadequate energy intake.
Individuals who experience pain, nausea, or diarrhea due to the side effects of radiation and chemotherapy may want to discuss treatments options with their doctor to ease these side effects.
Dietary tips for managing anorexia
- Serve food when the patient is hungry. A microwave oven often helps.
- Have the patient eat small meals every one to two hours, or time meals corresponding to when the patient feels best (typically early in the day).
- If only a little food is consumed by the patient, it should ideally be high in protein and calories. Avoid empty calories (i.e. foods without protein and nutrients).
- Add extra calories and protein to foods with the use of butter, skim milk powder, commercially prepared protein powder, honey, or brown sugar.
- Try to tempt the patient with tiny portions on small plates.
- Serve food in an attractive manner.
- Food is more likely to be eaten if it is served at frequent intervals unrelated to standard meal times.
- Avoid strong aromas if the patient finds them bothersome.
- Avoid liquids with meals to decrease problems of early satiety
- A small alcoholic drink of the patient's choice may help unless contraindicated.
- Consider flavors, consistency and quantity of food when preparing meals.
- Encourage eating with friends or family members; a meal in a social setting may help the patient to eat.
- Stimulate appetite with light exercise.
- Treat any underlying cause and, if a particular drug appears to be the cause, modify drug regimen.
- Have the patient take medications with high-calories fluids, i.e. commercial liquid supplements unless medication necessitates an empty stomach.
Often, patients may experience difficulty with eating due to upper gastrointestinal blockage such as problems with swallowing, esophageal narrowing, tumor, stomach weakness, paralysis, or other conditions that preclude normal food intake. In those circumstances, enteral nutrition may be administered through a tube into the gastrointestinal tract via the nose, or through surgically placed tubes into the stomach or intestines. If the gastrointestinal tract is working and will not be affected by the cancer treatments, then enteral support by feeding directly into the gut is preferable. Parenteral nutrition (most often an infusion into a vein) can be used if the gut is not functioning properly or if there are other reasons that prevent enteral feeding.
An appetite stimulant may be given such as megestrol acetate or dexamethasone. In clinical trials, both these medications appear to have similar and effective appetite stimulating effects with megestrol acetate having a slightly better toxicity profile. Fluoxymesterone has shown inferior efficacy and an unfavorable toxicity profile.
Alternative and complementary therapies
Depression may affect approximately 15-25% of cancer patients, particularly if the prognosis for recovery is poor. If anorexia is due to depression, there are antidepressant choices available through a physician. Counseling may be also be sought through a psychologist or psychiatrist to deal with depression.
St. John's Wort has been used as a herbal remedy for treatment of depression, but it and prescription antidepressants is a dangerous combination that may cause symptoms such as nausea, weakness, and may cause one to become incoherent. It is important to check with a dietitian or doctor before taking nutritional supplements or alternative therapies because they may interfere with cancer medications or treatments.
Keane, Maureen et al. What to Eat If You Have Cancer: A Guide to Adding Nutritional Therapy to Your Treatment
Nixon, Daniel W., M.D., Jane A. Zanca, and Vincent T. DeVita, The Cancer Recovery Eating Plan: The Right Foods to Help Fuel Your Recovery. New York:Times Books, 1996.
Quillin, Patrick and Noreen Quillin. Beating Cancer With Nutrition-Revised. Sun Lakes, AZ: Bookworld Services, 2001.
Kant, Ashima et al. "A Prospective Study of Diet Quality and Mortality in Women." JAMA 283 (16) (2000): 2109-2115.
Loprinzi, C.L. et al. "Randomized comparison of megestrol acetate versus dexamethasone versus fluoxymesterone for the treatment of cancer anorexia/cachexia." Journal of Clinical Oncology 17 (10) (1999): 3299-306.
Singletary, Keith. "Diet, Natural Products and Cancer Chemoprevention." Journal of Nutrition 130 (2000): 465S-466S.
Willett, Walter C. "Diet and cancer." The Oncologist 5(5)(2000): 393-404.
National Center for Complementary and Alternative Medicine (NCCAM), 31 Center Dr., Room #5B-58, Bethesda, MD 20892-2182. (800) NIH-NCAM, Fax (301) 495-4957. <http://nccam.nih.gov>.
The National Cancer Institute (NCI). For information contact the Public Inquiries Office: Building, 31, Room 10A31, 31 Center Drive, MSC 2580, Betheseda, MD 20892-2580 USA. (301) 435-3848, 1-800-4-CANCER. <http://cancer.gov/publications>, <http://cancernet.nci.nih.gov>.
American Institute for Cancer Research, 1759 R Street N.W., Washington, D.C. 20009. (800) 843-8114 or (202) 328-7744. <http://www.aicr.org, e-mail:firstname.lastname@example.org>.
Crystal Heather Kaczkowski, MSc.
—A condition frequently observed in cancer patients characterized by a loss of appetite or desire to eat.
—A term for diseases in which abnormal cells divide without control. Cancer cells can invade nearby tissues and can spread through the bloodstream and lymphatic system to other parts of the body.
—A yeast-like fungal infection occuring on the skin or mucous membranes, i.e. mouth.
—Chemotherapy kills cancer cells using drugs taken orally or by needle in a vein or muscle. It is referred to as a systemic treatment due to fact that it travels through the bloodstream and kills cancer cells outside the small intestine.
Malignant (also malignancy)
—Meaning cancerous; a tumor or growth that often destroys surrounding tissue and spreads to other parts of the body.
—Also called radiotherapy; uses high-energy x-rays to kill cancer cells.
—A feeling of fullness or satisfaction during or after food intake.
—An excess of nitrogenous substances in the blood that are toxic and usually excreted by the kidneys.