Without the right mix of vitamins, minerals and nutrients, a person will become malnourished.
While this can occur when a person is undernourished, and not getting enough nutrients or calories, it can also be due to overnourishment, aka, taking in too many calories, according to the Academy of Nutrition and Dietetics. And falling short on even one vitamin can cause malnutrition, per the U.S. National Library of Medicine (NLM).
The consequences of malnutrition are serious. In older adults, for instance, it can lead to a weakened immune system, increased risk of death and decreased bone mass, according to the Mayo Clinic. And in kids, it causes developmental delays and other major problems, per the Academy of Nutrition and Dietetics.
In the United States, 1 percent of children have chronic malnutrition, according to Johns Hopkins Medicine. Older adults are also at a high risk, particularly seniors in the hospital — up to 65 percent may have malnutrition, per the Alliance for Aging Research.
How to Prevent Malnutrition
To prevent malnutrition, start by identifying the causes and symptoms of this condition.
It's reasonable that not getting enough nutrients can cause malnutrition. But eating a lot of calories can lead to a person falling short on important nutrients — that is, where calories come from makes a difference to overall nutrition. Being overnourished can lead to being overweight or obese.
According to Johns Hopkins Medicine, malnutrition can occur due to:
- Not getting enough nutrients
- Excreting nutrients at a faster rate than they're replaced
- An unbalanced diet
- Taking too many vitamins or dietary replacements
Certain conditions — such as cancer — can also lead to a person becoming malnourished, according to the NLM. Medications, too, can prevent a person from properly absorbing nutrients, per the Merck Manual.
Some life stages, such as infancy, childhood, adolescence, pregnancy and old age, demand more nutrition than others, and people in these groups might be at a higher risk for malnutrition. Poverty increases the risk of malnutrition, according to the World Health Organization (WHO).
Weight loss is one very common symptom of malnutrition, according to the NLM.
Malnutrition can also lead to skin changes — including dryness, rashes and being quick to bruise — as well as achy joints, a weakened immune system and listlessness, per Johns Hopkins Medicine.
Common Vitamin Deficiencies
Malnutrition due to undernutrition can lead to falling short on essential vitamins and minerals, according to the Merck Manual. This type of malnutrition can lead to several diseases and conditions, including rickets, pellagra and eye conditions.
Deficiencies that are particularly common with malnutrition include:
If you don't get enough iron, your body won't make enough hemoglobin for your red blood cells. Since hemoglobin carries oxygen to cells, the end result is feeling tired, pale and dizzy, among other symptoms, according to the Mayo Clinic.
Women, children, blood donors and vegetarians are at an increased risk for this deficiency, per the Mayo Clinic. Supplements can help, but see your doctor before taking them to ensure you have the correct dose (and there isn't an underlying problem that needs treatment), per guidance from the Mayo Clinic.
Vitamin D Deficiency
A long-term deficiency in the sunshine vitamin can lead to a childhood condition known as rickets, which is characterized by skeletal deformities due to soft bones, according to the Harvard T.H. Chan School of Public Health.
In adults, it can lead to osteomalacia, a bone condition that can be treated through vitamin D supplementation, per the Harvard T.H. Chan School of Public Health.
Vitamin A Deficiency
Not getting enough vitamin A can lead to a condition known as xerophthalmia, which begins with dry eyes but can eventually lead to total blindness if the deficiency isn't corrected, according to the Harvard T.H. Chan School of Public Health.
Vitamin A deficiency can make childhood infections more serious — even leading to death — and makes it harder to fight off infections, according to the WHO.
People in the United States are only rarely low on vitamin A, but it's more common in developing countries, per the Office of Dietary Supplements.
Niacin is a B vitamin that helps your body transform food into energy, according to the Mayo Clinic. Not getting enough niacin can cause pellagra, which is characterized by diarrhea, rashes on the skin and, if the deficiency isn't corrected, dementia and death, according to a January 2021 book from StatPearls, which provides medical information for health care practitioners.
Iodine deficiency, which is more common in women, can lead to goiters, infertility and thyroid cancer, according to Temple Health. Children of people with iodine deficiency may have learning disabilities.
Treatment Strategies for Malnutrition
Treatment of this condition generally involves a two-pronged approach.
1. Replace Missing Nutrients
To combat malnutrition, people must have a well-balanced diet.
With undernutrition, upping the number of calories consumed is recommended, per the Merck Manual — eating several small but balanced meals during the day can help achieve this goal.
Nutritional supplements, or liquid nutrition, might be needed, depending on the severity of the malnutrition. In severe cases, hospitalization might be necessary.
2. Treat Underlying Conditions
If an underlying medical condition or medication caused the malnutrition, then it must be addressed to prevent ongoing loss of nutrients. Medical conditions ranging from Alzheimer's disease to eating disorders can also lead to malnutrition, per the Academy of Nutrition and Dietetics.
Other factors can also play a role: Malnutrition can be the result of not being able to afford or access nutritious food.
The proper interventions, therefore, may depend on the underlying cause of malnutrition. In many cases, registered dietitians can provide support, but organizations (both charitable and governmental) may also play an important role.
Chronic lack of nutrients might also cause a medical condition that needs treatment.
- Academy of Nutrition and Dietetics: "What is Malnutrition"
- U.S. National Library of Medicine: "Malnutrition"
- Mayo Clinic: "Senior health: How to prevent and detect malnutrition"
- Johns Hopkins Medicine: "Malnutrition"
- Alliance for Aging Research: "Malnutrition in Older Adults"
- Merck Manual: "Undernutrition"
- World Health Organization: "Malnutrition"
- Mayo Clinic: "Iron deficiency anemia"
- StatPearls: "Vitamin D Deficiency"
- Harvard T.H. Chan School of Public Health: "Vitamin D"
- NLM: "Vitamin A"
- Harvard T.H. Chan School of Public Health: "Vitamin A"
- WHO: "Vitamin A deficiency"
- Office of Dietary Supplements: "Vitamin A"
- Mayo Clinic: "Niacin"
- StatPearls: "Niacin Deficiency"
- Temple Health: "Iodine Deficiency"