Updated November 1, 2021

Malnutrition is a condition that occurs when there is an imbalance between what a person eats and the nutrients they need to maintain good health.

It’s associated with a weakened immune system, muscle wasting, and delayed wound healing, and it costs the U.S billions of dollars each year in medical costs (1).

Malnutrition can affect all age groups but it’s much more prevalent among older adults.

This article lists five risk factors of malnutrition in older adults and some ways to help treat and prevent malnutrition.

malnutrition in older adults

1. Poor oral health

Poor oral health is a major risk factor of malnutrition in older adults.

Oral health problems — whether from missing teeth, ill-fitting dentures, cavities, or infection — can cause difficulty eating and lead to inadequate nutrition intake (2).

Older adults who are poor, lack insurance, disabled, or living in a nursing home are at an increased risk of poor oral health.

Older adults with chewing problems may be prescribed a texture-modified diet, but the mashing and blending of foods can reduce the appeal and taste, further contributing to low appetite and food intake (3, 4).

2. Cognitive impairment

Several studies show that cognitive impairment is associated with malnutrition in older adults (5, 6).

Cognitive impairment is when a person has problems remembering, communicating or making decisions that affects their everyday life.

While some cognitive decline is expected as part of the normal aging process, severe cognitive impairment can lead to an inability to perform activities of daily living such as eating, ultimately affecting food intake (7).

People with cognitive impairment are at an increased risk of developing Alzheimer’s disease or other forms of dementia (8).

Other conditions such as stroke, traumatic brain injury, and developmental disabilities can also cause cognitive impairment.

3. Polypharmacy

Polypharmacy is commonly defined as using multiple medications concurrently to manage health problems, such as diabetes and high cholesterol.

Among older adults, polypharmacy is common with the highest number of drugs taken by those living in nursing homes (9).

Polypharmacy is associated with several negative health consequences, including malnutrition.

One study found that 50% of those taking 10 or more medications were found to be malnourished or at risk of malnutrition (10).

Many drugs can contribute to poor nutritional status by causing loss of appetite, nausea, diarrhea, and taste changes (11).

4. Depression

Depression is an often-overlooked risk factor of malnutrition in older adults.

Older adults often experience physiological and environmental changes that are associated with depression, such as isolation, loneliness, and poor financial status (12).

Depressed older adults often lose their appetite and experience unintended weight loss resulting in an increased risk of malnutrition.

In one study, the risk of depression in older adults with malnutrition was more than 15 times higher than in non-depressed older adults (13).

Similarly, another study found symptoms of depression in older adults as a predictor of malnutrition (14).

5. Overly strict therapeutic diets

Overly strict therapeutic diets can lead to poor nutrition intake in older adults.

A therapeutic diet is typically prescribed for the purpose of controlling the intake of certain foods or nutrients to improve health.

For instance, a person with type 2 diabetes may be prescribed a diabetic therapeutic diet to help control their blood sugar levels.

For frail older adults, however, a therapeutic diet does not offer enough benefits to justify its use (15).

Many older adults find therapeutic diets unpalatable, leading them to eat less.

Consequently, strict therapeutic diets can lead to unintended weight loss and malnutrition.

With that said, liberalized diets are associated with increased food and beverage intake in older adults (15).

How to prevent and treat malnutrition

Understanding the risk factors associated with malnutrition is the best way to prevent malnutrition.

Registered dietitians can identify malnutrition risk factors by conducting a thorough and comprehensive nutrition assessment.

Based on this assessment, the dietitian can implement early nutrition interventions to reduce the risk of or prevent malnutrition.

For older adults who are already diagnosed with malnutrition, a dietitian can implement nutrition interventions aimed at treating the underlying cause of malnutrition.

For example, a dietitian may liberalize a strict therapeutic diet for someone who has poor intake.

Or a dietitian may consult a pharmacist to conduct a medication review on a resident who reports a poor appetite and taste changes to determine what — if any — medications may be causing these symptoms.

Any medications identified as causing these symptoms could have their dose reduced, swapped for an alternative with fewer side effects, or discontinued, depending on the pharmacist’s recommendation.

But in some cases like end-of-life care, treating malnutrition may not be possible.

In these instances, the dietitian can focus on minimizing the underlying signs and symptoms of malnutrition.

In either case, the nutrition intervention should keep the resident or patient at the center of the care planning and decision-making process.

The bottom line

Malnutrition is a condition where the body does not get enough of the nutrients it needs.

Older adults are at an increased risk of malnutrition for many reasons including poor oral health, cognitive decline and polypharmacy.

Depression and overly strict therapeutic diets can also contribute to malnutrition in older adults.

As such, it’s important for registered dietitians and other members of the interdisciplinary health care team to recognize the risk factors of malnutrition to provide and support appropriate nutrition interventions.


Gavin Van De Walle, MS, RD
Gavin Van De Walle, MS, RD

Gavin Van De Walle, MS, RD is a registered dietitian with a master's of science in human nutrition and bioenergetics. Gavin specializes in nutrition for older adults and regulations surrounding long-term care as they relate to food and nutrition.