Medical nutrition therapy

Related Terms

Diet, dieticians, eating disorders, enteral feedings, MNT, nutritional therapy, parenteral feedings, tube feedings.

Background

Medical nutrition therapy (MNT) includes a wide variety of treatments based on the nutritional status of the patient. The intensity of the therapy varies greatly, ranging from a few changes in dietary intake to tube or intravenous feeding.
Medical nutrition therapy may be useful in treating or controlling heart disease, diabetes, AIDS, cancer, kidney disease and many other health related conditions. While often used as part of a palliative care treatment, relatively healthy people may also use this therapy for minor dietary adjustments. Complementary nutrition therapy optimizes nutritional health in order to enhance medical care and treatment. Medical nutrition therapy is not a cure for terminal illness but can improve a patient's quality of life.
According to The American Dietetic Association medical nutrition therapy and lifestyle counseling are integral components of medical treatment for the management of selected conditions. Numerous chronic medical conditions respond to medical nutrition therapy; however, pharmacotherapy may be needed to achieve control. In some cases, medical nutrition therapy and pharmacotherapy may need to be initiated simultaneously. Medical nutrition therapy is critical to the management of a variety of chronic diseases, is effective in managing disease, and is cost-effective. Strong evidence advocating certain types of medical nutrition therapy lies in the extremely high usage of parenteral and enteral nutritional formulas in many health care settings today. Parenteral feedings may allow people who are not able to take any food orally to get the nutrients that they need to survive.
Promising uses of medical nutrition therapy for the future reside in a vast array of conditions, such as supplying proper nutrients to people with HIV/AIDS and cancer, or possibly helping to decrease the prevalence of type II diabetes.

Theory / Evidence

Society may be aware of the impact diet has on disease prevention but far fewer people are aware that changes in diet may be able to help speed the recovery process and control diseases. The scope of medical nutrition therapy makes it very challenging to draw any firm conclusions regarding its safety or efficacy, as it may be practiced in any number of ways for a variety of conditions. Nevertheless, this therapy appears relatively safe when used under the supervision of a qualified healthcare professional and/or dietician.
Patients with a variety of medical conditions may benefit from medical nutrition therapy. Conditions and symptoms that have been studied include dry skin, joint pain, indigestion, heartburn, gas, bloating, diarrhea, constipation, hypertension, gestational diabetes, irritable bowel syndrome, gastrointestinal problems, diabetes, high cholesterol, insulin resistance, depression, thyroid disease, food allergies, chronic fatigue, menopausal symptoms, HIV/AIDS, kidney failure, eating disorders, pregnancy, wound healing, psoriasis, cardiovascular disease, obesity, and post-surgical therapy.
Studies conducted on the effectiveness of medical nutrition therapy in the treatment of diabetes have shown positive results. Medical nutrition therapy has not only improved diabetes, but also the well being of the patients treated. Today there is no one "diabetic" diet. The recommended diet is a dietary prescription based on nutrition assessment and treatment goals of an individual patient. Thus, medical nutrition therapy for people with diabetes is often individualized, with consideration given to usual eating habits and other lifestyle factors.
Brown et al. reported on five cases of medical nutrition therapy used for the treatment of psoriasis. This condition has no known cure, and the multiple treatments currently available only attempt to reduce the severity of symptoms. The dietary study protocol included a diet of fresh fruits and vegetables, small amounts of protein from fish and fowl, fiber supplements, olive oil, and avoidance of red meat, processed foods, and refined carbohydrates. Saffron tea and slippery elm bark water were consumed daily. The five psoriasis cases, ranging from mild to severe at the study onset, improved on all measured outcomes over a six-month period. These results suggest a dietary regimen may be an effective medical nutrition therapy for the complementary treatment of psoriasis; however, further well-designed trials are warranted to confirm these results.
Probiotics, or "friendly" bacteria that are normally present in the intestine and help to promote healthy digestion, have been studied as a potential form of medical nutrition therapy. Brown et al. (2004) conducted a detailed literature review (from 1950 through February 2004) of English-language articles to find articles showing a relationship between probiotic use and medical conditions. Medical conditions that have been reportedly treated or have the potential to be treated with probiotics include diarrhea, gastroenteritis, irritable bowel syndrome, inflammatory bowel disease (Crohn's disease and ulcerative colitis), cancer, depressed immune function, inadequate lactose digestion, infant allergies, failure-to-thrive, hyperlipidemia, hepatic diseases, Helicobacter pylori infections, genito-urinary tract infections, and others. The authors concluded that the use of probiotics should be further investigated for possible benefits and side effects in patients affected by these medical conditions.
Although eating disorders fall under the category of psychiatric diagnoses, there are a number of nutritional and medical issues that require the expertise of a registered dietitian. Medical nutrition therapy provided by a registered dietitian trained in the area of eating disorders may play a significant role in the treatment and management of eating disorders.
According to the American Dietetic Association and the Canadian Dietetic Association, the goals of medical nutrition therapy in HIV include early assessment and treatment of nutrient deficiencies, maintenance and restoration of lean body mass, and support for activities of daily living and quality of life. The maintenance and restoration of nutritional stores are closely interrelated and interdependent with each of the other recommended medical therapies. There is a recent push for HIV/AIDS patients to have access to the services of a registered dietitian to provide medical nutrition therapy. Additionally, government health-related agencies, national AIDS-related organizations, and private industries have been encouraged to provide funding sources and support to the issue of research in nutrition-related problems and interventions in HIV/AIDS; however, further research is needed in this area.

Author information

This information has been edited and peer-reviewed by contributors to the Natural Standard Research Collaboration (www.naturalstandard.com).

Bibliography

American Dietetic Association.
Beto JA, Bansal VK. Medical nutrition therapy in chronic kidney failure: integrating clinical practice guidelines. J Am Diet Assoc. 2004 Mar;104(3):404-9.
Brown AC, Hairfield M, Richards DG, et.al. Medical Nutrition Therapy as a Potential Complementary Treatment for Psoriasis-Five Case Reports. Altern Med Rev 2004;9(3):297-307.
Brown AC, Valiere A. Probiotics and Medical Nutrition Therapy. Nutr Clin Care. 2004;7:56-68.
Kulkarni K. Diets do not fail: the success of medical nutrition therapy in patients with diabetes. Endocr. Pract. 2006 Jan-Feb;12 Suppl1:121-3.
Nutrition recommendations and principles for people with diabetes mellitus. Diabetes Care. 1994 May;17(5):519-22.
Position of the American Dietetic Association and the Canadian Dietetic Association: nutrition intervention in the care of persons with human immunodeficiency virus infection. J Am Diet Assoc. 1994 Sep;94(9):1042-5.
Position of the American Dietetic Association: medical nutrition therapy and pharmacotherapy. J Am Diet Assoc. 1999 Feb;99(2):227-30.
Position of the American Dietetic Association: nutrition intervention in the treatment of anorexia nervosa, bulimia nervosa, and eating disorders not otherwise specified (EDNOS). J Am Diet Assoc. 2001 Jul;101(7):810-9.

Technique

Medical nutrition therapy is usually initiated by a qualified physician who refers a patient to a dietician. Dieticians, trained in the science of food and nutrition, provide patients and their caretakers with nutritional services and advice.
Dieticians work with medical teams to assess a patient's needs and devise a detailed diet plan that will suit that patient's needs. Dieticians may also provide diet counseling or suggest other changes that will help treat specific disease conditions.
One type of medical nutrition therapy is total parenteral nutrition (TPN). TPN is generally dripped through a needle or catheter into a vein for 10-12 hours, once a day, five times a week. This therapy is used for patients who cannot, or should not, get their nutrition through eating. It may include a combination of sugar and carbohydrates (for energy), proteins (for muscle strength), lipids (fat), electrolytes, and trace elements, depending on the patient's condition. Electrolytes, which may help the heart, muscles, and nerves work properly and prevent dehydration, include sodium, potassium, chloride, phosphate, calcium, and magnesium. Trace elements may include zinc, copper, manganese, and chromium. The length of treatment will depend on how the patient responds to the medication. Parenteral treatments are generally administered in the hospital.
Enteral nutrition formulas are used as nutritional replacements for patients who are unable to get enough nutrients in their diet. These formulas are taken by mouth or through a feeding tube and are used to provide energy and to form substances needed for normal body functions. For patients taking the oral liquid form of enteral nutrition, these preparations are generally in ready-to-use form. No dilution is needed unless directed by a physician. The preparation should be shook well before opening, and refrigerated after opening. Most formulas may be able to be kept in the refrigerator for 1 to 2 days. For patients using the powder form of this preparation, the instructions for mixing on the package should be followed carefully. Enteral treatments may be taken at home, or in the hospital, following a doctor's instructions.
Medical nutrition therapy can consist of individual or group sessions, integrating nutrition and lifestyle counseling.