What group of people are most at risk from malnourishment?

January 10, 2026 •

3 min read

According to the World Health Organization, in 2022, approximately 390 million adults were underweight globally, while 2.5 billion were overweight. Malnourishment, which includes both undernutrition and overnutrition, affects people across all demographics, but certain groups are disproportionately vulnerable due to specific physiological, social, and economic factors.

Quick Summary

This article examines the primary demographic groups most susceptible to malnourishment, detailing why infants, children, pregnant women, the elderly, and those with chronic diseases face heightened risks. It explores the diverse factors contributing to their vulnerability and outlines the specific challenges they face in maintaining adequate nutritional health.

Key Points

Infants and Children: Are highly vulnerable due to rapid growth, weak immune systems, and specific nutrient needs in the first 1,000 days of life.
Pregnant and Lactating Women: Experience increased nutritional demands, and deficiencies can lead to complications for both mother and child, often amplified by socioeconomic factors.
Older Adults: Face higher risks from reduced appetite, changes in body function, social isolation, and institutionalization, all of which contribute to undernutrition.
Individuals with Chronic Illnesses: Have compromised nutritional status due to diseases that affect appetite, absorption, or increase metabolic needs, such as HIV/AIDS, cancer, and gastrointestinal disorders.
The Underserved and Impoverished: Experience higher rates of malnourishment due to poor food access, sanitation, and education, perpetuating a cycle of poor health.
Malnutrition is Not Always Visible: It can manifest as both undernutrition and overnutrition, and a person can be overweight yet still deficient in essential vitamins and minerals.
Prevention is Key: Effective interventions require early action, particularly focusing on optimal nutrition for pregnant women and young children to prevent long-term developmental issues.

Infants and Young Children

Infants and young children are particularly vulnerable to malnourishment due to their rapid growth and developing immune systems, especially during the critical first 1,000 days of life. Factors like inadequate breastfeeding, poor sanitation, and frequent infections contribute to undernutrition. Undernutrition can manifest as chronic undernutrition (stunting), impacting long-term development, or acute undernutrition (wasting), increasing the risk of death. In 2022, an estimated 149 million children under five were stunted globally.

Pregnant and Lactating Women

Increased nutritional demands during pregnancy and lactation heighten a woman’s risk of malnutrition, affecting both her health and fetal development. Deficiencies in nutrients like iron, folic acid, and iodine are common and can lead to anemia, preterm birth, and low birth weight. Socioeconomic factors and the intergenerational cycle of malnutrition also play significant roles.

Older Adults

Malnutrition is a significant issue among the elderly due to age-related physical changes affecting appetite and taste, social isolation, chronic diseases and their medications, and the challenges of hospitalization or institutional care.

Individuals with Chronic Illnesses and Medical Conditions

Chronic illnesses increase the risk of malnourishment by increasing nutritional needs, impairing nutrient absorption, or reducing appetite. Conditions like HIV/AIDS, gastrointestinal disorders (e.g., Crohn's, celiac disease), mental health disorders (e.g., dementia, depression), and cancer can all contribute to poor nutritional status.

Comparison of Malnutrition Risk Factors in Vulnerable Groups


Risk Factor	Infants/Young Children	Pregnant Women	Elderly Adults	Chronically Ill Individuals
Increased Nutritional Need	High demand for growth and development	Heightened requirements for fetus and maternal health	Stable or reduced metabolic rate, but nutrient needs persist	Depends on the condition (e.g., increased in HIV/AIDS)
Reduced Appetite	Often due to illness, infections, or improper weaning	May be affected by morning sickness, hormonal changes	Common, known as 'anorexia of aging'	Caused by disease, medication, or mental health issues
Impaired Absorption	Diarrhea and other frequent infections	Less common, but possible with certain conditions	Altered gastrointestinal function with age	Chronic bowel illnesses like Crohn's and celiac disease
Socioeconomic Influence	Strong link, especially in low-income settings	Access to nutritious food is a major determinant	Can be worsened by limited income	Often linked with poverty and limited healthcare access
Isolation/Care Environment	High risk in neglected children or institutional care	Not a direct risk, but societal support is key	Significant risk, especially in care homes	Patients with reduced mobility or requiring long-term care

Conclusion

While malnourishment can affect anyone, specific groups are far more susceptible due to a combination of physiological, social, and economic factors. The young, the elderly, pregnant women, and those battling chronic illnesses face unique challenges that put their nutritional health at severe risk. Addressing malnourishment effectively requires targeted interventions that consider the specific needs of these vulnerable populations. A multifaceted approach encompassing better access to nutritious food, improved healthcare, nutritional education, and support for the disadvantaged is crucial to combating this global health challenge and breaking the cycle of poverty and ill-health. Preventing malnutrition early in life and throughout adulthood is critical for ensuring better health outcomes and a more productive society.

Authoritative research from organizations like the World Health Organization (WHO) and UNICEF consistently highlights these groups. For further reading, see the WHO's factsheets on malnutrition [https://www.who.int/news-room/fact-sheets/detail/malnutrition].

Frequently Asked Questions

Malnourishment is a broad term that includes deficiencies, excesses, or imbalances in a person's nutrient intake. Undernutrition is a form of malnourishment caused by a lack of adequate nutrients, leading to issues like stunting, wasting, and vitamin deficiencies.

Pregnant women are at a higher risk because pregnancy significantly increases their need for calories, vitamins, and minerals to support both their own health and the growth of the fetus. Without proper intake, deficiencies can occur, leading to adverse outcomes like low birth weight and anemia.

No, malnourishment is a global issue affecting countries at all income levels. While undernutrition is more common in developing nations, overnutrition (overweight and obesity) is rising globally and is also considered a form of malnourishment.

Chronic illnesses can interfere with nutrient absorption, suppress appetite, and increase the body's metabolic needs. This can result in an imbalance where the body is unable to get or use the nutrients it needs to recover and stay healthy.

Yes, with early detection and effective nutritional intervention, elderly individuals can often recover from malnourishment. However, some effects can linger, so timely action is important.

Poverty is a primary driver of malnourishment, as it limits access to affordable, nutritious food, clean water, and adequate healthcare. It creates a vicious cycle where malnutrition hampers productivity and economic potential, further perpetuating poverty.

Early signs of malnourishment in a child include stunted growth, low body weight, fatigue, irritability, and frequent infections. Delayed physical and cognitive development can also occur with long-term undernutrition.