Medical nutrition therapy (MNT) is an evidence-based, individualized nutrition process meant to help treat certain medical conditions.

The term was introduced in 1994 by what is now the Academy of Nutrition and Dietetics, the largest organization of registered dietitian nutritionists (RDNs) and other credentialed food and nutrition professionals in the United States (1).

MNT is developed and implemented by an RDN with the approval of the patient’s doctor. MNT may be conducted in a hospital, in an outpatient clinic, or as part of a telehealth program.

This article reviews how medical nutrition therapy works and how it can aid some common medical conditions.

MNT is based on decades of medical research on the relationship between diet, nutrition, and health outcomes.

It’s vastly different from nutrition education, which provides basic nutrition information to the general public and isn’t intended to treat medical conditions.

On the other hand, MNT instructs individuals how to use their diet to best support their medical conditions. It not only addresses existing medical conditions but also attempts to lower the risk of new complications.

Steps and scope

To start this therapy, an RDN first performs a comprehensive nutrition assessment for an individual. They then develop a nutritional diagnosis, goal, and care plan, as well as specific nutrition interventions to help the person better manage or treat their condition (2).

The RDN provides repeated follow-up visits to support the person’s behavioral and lifestyle changes. This involves monitoring and evaluating progress, as well as any health or medication changes (2).

MNT is only provided by a qualified dietitian and can either be prescribed in a hospital or outpatient setting. It may start during a hospital admission and continue into an outpatient setting, as long as the patient is seeing an RDN.

MNT can range in complexity, from designing a reduced calorie diet for weight loss to prescribing a high protein diet to promote wound healing for patients with severe burns.

In severe cases, such as for people with cancer, an RDN can recommend tube or intravenous (IV) feeding to prevent malnutrition.

The duration of MNT varies. Typically, the therapy stays in place until the initial goal is achieved or the nutrition-related diagnosis is resolved. However, the plan can be adjusted as needed by the RDN and your medical team.

SUMMARY

MNT is an evidence-based nutrition therapy led by a registered dietitian nutritionist (RDN) to help treat medical conditions. It occurs in a hospital or outpatient setting and involves a comprehensive assessment, nutritional diagnosis, and treatment plan.

MNT can be a very effective component of the overall management plan for a number of common diseases.

Diabetes

Diabetes is a condition in which your blood sugar levels become too high. This can either be type 1, in which your pancreas produces too little insulin, or type 2, in which your body doesn’t properly use insulin to regulate blood sugar (3).

If left untreated, diabetes can lead to complications like nerve and vision damage, stroke, kidney disease, poor circulation, heart disease, and gum infections (4).

Research shows that MNT can help control diabetes (1, 5, 6, 7).

For example, studies note that this therapy can lower certain markers of diabetes, such as hemoglobin A1c (HbA1c), which is an indicator of long-term blood sugar control (8, 9, 10).

It’s also effective at managing gestational diabetes, a high blood sugar condition that occurs during pregnancy and requires dietary changes (11).

Treatment usually involves an RDN teaching carb counting and portion control, a technique that helps control blood sugar by keeping carb intake consistent — since carbs affect blood sugar more than other nutrients (6).

Heart disease

Heart disease refers to several conditions that affect heart function, such as irregular heartbeat, high blood pressure, and plaque buildup in your arteries. Left untreated, it can lead to heart attack, stroke, aneurysm, heart failure, and even death (12, 13).

Research demonstrates that MNT can reduce risk factors for heart disease, such as LDL (bad) cholesterol, triglycerides, and high blood pressure (14, 15).

A dietitian may recommend that you adhere to a diet low in saturated fat, cholesterol, sodium, and inflammatory foods (15). Emphasis may be placed on increasing fruits and vegetables and following a more plant-based diet.

As obesity is a risk factor for heart disease, an RDN may also encourage lifestyle changes to achieve and maintain a healthy weight, including increasing physical activity and getting adequate sleep (16).

Cancer

Cancer is a disease in which abnormal cells start to divide uncontrollably. It can affect any part of your body, such as your blood, bones, or organs (17).

One of the primary reasons that a dietitian may be involved in cancer treatment is to help individuals with poor appetite, which is a common symptom of chemotherapy or cancer medications (18).

Radiation therapy may also damage the gastrointestinal lining and make it painful to eat or difficult to digest foods.

As such, many people with cancer struggle to eat enough and are at risk of malnutrition. An RDN may recommend high calorie nutritional shakes or other fat- and protein-rich foods that are easy to consume and digest (18).

In severe cases, an RDN may recommend tube or IV feeding.

Digestive conditions

People with ulcerative colitis, Crohn’s disease, irritable bowel syndrome (IBS), and Celiac disease, as well as those who’ve lost part of their intestinal tract due to surgery, can all benefit from MNT (19).

These digestive ailments can lead to poor nutrient absorption, malnutrition, weight loss, a buildup of toxins in the colon, and inflammation (20).

A dietitian can develop a tailored MNT plan to fit the needs of a specific digestive condition, reduce symptoms, and improve quality of life.

For example, someone with inflammatory bowel disease (IBD) may benefit from a supervised elimination diet, in which certain foods are excluded and slowly added back to their diet to identify those that trigger symptoms (21, 22).

Kidney disease

Untreated kidney disease, in which your blood is not filtered normally, can lead to complications like high levels of calcium and potassium in the blood, low iron levels, poor bone health, and kidney failure (23, 24).

MNT is useful because most people with kidney disease may need to adjust their diet.

For example, some should limit their intake of nutrients like protein, potassium, phosphorus, and sodium, while others may need to adhere to certain fluid restrictions. These needs vary widely depending on the stage or severity of the disease (25).

Treating high blood pressure is often central to MNT for someone with kidney issues, as high blood pressure can increase your risk of this disease (26).

SUMMARY

MNT can be used to treat numerous medical conditions, such as heart disease, diabetes, cancer, kidney disease, and digestive issues.

Like other medical treatments, MNT has an appropriate time and place.

MNT is prescribed after an in-depth evaluation by an RDN determines that you have a medical condition that can be improved by adhering to this method.

As such, MNT isn’t always necessary. For example, someone admitted to the hospital for a procedure who is determined to be eating well, adequately nourished, and not at risk of malnutrition may not require MNT.

In general, a doctor orders a nutritional assessment from an RDN when a patient is admitted to the hospital. In an outpatient setting, an RDN may be consulted if a doctor suspects a nutrition-related concern.

MNT is common across various developed regions, including North America, New Zealand, Japan, and parts of Europe (27, 28, 29).

SUMMARY

MNT is determined to be appropriate only after a thorough nutritional evaluation by a dietitian in a hospital or outpatient setting.

MNT is a well-established, nutritional approach to alleviating, managing, and even treating certain medical conditions.

It has been proven effective for many common chronic illnesses, such as heart disease, diabetes, cancer, kidney disease, and digestive disorders.

Remember that you should only seek this treatment after a thorough evaluation by a dietitian. Always consult an RDN for individualized MNT guidance.