What Is Malnutrition?

Malnutrition is a common, high-risk condition that must be addressed quickly and comprehensively. Malnutrition means unbalanced nutrition. It includes both undernutrition and overnutrition. When most people think of malnutrition, they usually picture undernutrition, which can be caused by a lack of calories, protein or other nutrients. This occurs frequently in areas of the world without adequate access to food and clean drinking water.

Overnutrition comes from eating too many calories. Someone can eat more calories than their body needs and be malnourished at the same time. They may not be eating enough nutritious foods such as fruits, vegetables, whole grains, lean protein, beans, low-fat dairy, nuts and seeds. This can result in vitamin, mineral or protein deficiencies. In the United States, this is more common in impoverished areas with limited access to healthful foods.

Malnutrition in children, especially young children, can lead to stunted growth, developmental delays and more frequent illness due to poor immune function.

Clinical malnutrition is when a hospital patient becomes malnourished. There are many reasons why someone in the hospital may not be getting enough nutrition. For example, their body may require more nutrition than usual, or they may not be able to absorb the nutrients they eat. Malnutrition also can be the result of an eating disorder, organ failure or severe infection or physical trauma such as a head injury. Some hospital patients need to receive nutrition through a tube inserted into their stomach or intravenous (IV) nutrition.

Malnutrition frequently occurs in the older adult population, especially in those with dementia or Alzheimer’s disease. Tooth loss and other dental issues, loss of appetite and functional decline are contributing factors to malnutrition among older adults. The Centers for Medicare & Medicaid Services requires long-term care facilities to employ registered dietitian nutritionists to manage the nutrition care of residents.

It is important that malnutrition is diagnosed in a timely manner. When a hospital patient becomes malnourished their medical treatment and recovery are affected. Research shows that malnutrition increases the length of stay, health care costs and the risk of death. Hospitals are required to screen for malnutrition within 24 hours of admission.

Registered dietitian nutritionists make recommendations and work with the health care team to help patients receive the nutrition they need. RDNs assess malnutrition using weight history, dietary intake, lab values and a physical exam. A nutrition-focused physical exam involves checking for body fat and muscle loss, fluid accumulation and hand grip strength.