Who Does Malnutrition Affect and Why?

November 15, 2025 •

4 min read

In 2022, nearly half of deaths among children under the age of five were linked to undernutrition, showing that malnutrition is a severe global health challenge. While it is often associated with starvation, the term actually covers deficiencies, excesses, and imbalances in nutrient intake and affects populations across all income levels.

Quick Summary

Malnutrition impacts vulnerable groups like children, pregnant women, the elderly, and the chronically ill due to inadequate food access, disease, and socioeconomic factors. The condition includes undernutrition, micronutrient deficiencies, and overnutrition, and its causes range from poverty to limited health education and poor sanitation.

Key Points

Vulnerable Populations: Infants, children, pregnant women, the elderly, and those with chronic illnesses are most susceptible to malnutrition.
Multiple Forms: Malnutrition includes undernutrition (stunting, wasting), micronutrient deficiencies, and overnutrition (overweight, obesity).
Socioeconomic Roots: Poverty, food insecurity, gender inequality, and low parental education are key drivers of malnutrition globally.
Severe Health Impacts: Malnutrition weakens the immune system, impairs cognitive development, and can lead to irreversible long-term health problems and increased mortality.
Environmental and Systemic Causes: Climate change, conflict, poor sanitation, and inadequate healthcare systems are major contributing factors, especially in low-income regions.
Double Burden of Malnutrition: Many countries and even families face the coexistence of both undernutrition and overnutrition, which complicates public health interventions.
Early Intervention is Crucial: The first 1,000 days from conception to a child's second birthday are a critical window for intervention to prevent the lifelong effects of malnutrition.

Malnutrition's Broad Reach: Who Is Affected?

Malnutrition is not a singular condition but a complex health issue that manifests in various forms across different demographics. It is a persistent global challenge, with no country left unaffected. From undernourished children in low-income nations to overweight individuals in affluent societies, the spectrum of who does malnutrition affect and why is surprisingly wide.

Vulnerable Groups for Undernutrition

Undernutrition, characterized by a deficiency of energy and nutrients, disproportionately impacts certain populations due to heightened nutritional needs or poor access to food.

Children and Infants: The first 1,000 days of a child's life are critical, as nutrition directly influences their physical and cognitive development. Children are highly susceptible to the effects of malnutrition, including stunting (low height-for-age) and wasting (low weight-for-height), which can have irreversible, lifelong consequences. Nearly half of global deaths in children under five are linked to undernutrition.
Pregnant and Breastfeeding Women: This group has increased nutritional demands to support both their own health and that of their baby. A malnourished mother is more likely to give birth to a malnourished baby, perpetuating an intergenerational cycle of poverty and poor health. Women and girls also face a “gender nutrition gap” in many cultures, eating last and least within households.
The Elderly: Factors such as reduced mobility, institutionalization, decreased appetite, and impaired nutrient absorption make older adults a high-risk group for undernutrition. This can lead to weakened immunity, slow wound healing, and impaired mental function.
The Chronically Ill: Diseases like cancer, HIV/AIDS, or conditions causing malabsorption (such as Crohn's disease) can interfere with nutrient absorption or increase the body's caloric needs, leading to malnutrition. Hospitalized patients are also at a higher risk.

Populations at Risk of Overnutrition

Overnutrition—the overconsumption of nutrients leading to overweight, obesity, and related diseases—is also a form of malnutrition that impacts millions worldwide.

Low-Income Communities in Developed Countries: In these areas, nutritious, fresh foods are often more expensive and less accessible than energy-dense, processed foods high in fats and sugars. This can lead to the 'double burden' of malnutrition, where overnutrition coexists with micronutrient deficiencies.
Individuals with Sedentary Lifestyles: Increased urbanization and reliance on sedentary occupations contribute to a lower energy expenditure, making overnutrition more likely.

Socioeconomic and Environmental Causes of Malnutrition

Beyond individual physiology, broader systemic issues determine who experiences malnutrition and why.

Poverty and Economic Inequality: Poverty is the most significant driver of malnutrition. It limits the ability of families to afford diverse and nutritious foods, trapping them in a vicious cycle of ill-health and reduced productivity that further slows economic growth. A healthy diet remains unaffordable for a large portion of the global population.
Poor Sanitation and Unclean Water: A lack of access to clean water and sanitation facilities increases the risk of infectious diseases like diarrhea, which prevent the body from absorbing essential nutrients and are a major cause of death among malnourished children.
Conflict and Disasters: Humanitarian crises and natural disasters disrupt food production and access, leading to widespread food insecurity, particularly affecting displaced and refugee populations.
Limited Education: Inadequate knowledge about proper nutrition, particularly among mothers, can lead to poor feeding practices for children. Higher maternal education levels are linked to better health and nutritional outcomes for children.
Climate Change: Extreme weather events like droughts and floods disrupt agriculture, leading to failed harvests, food shortages, and higher food prices, disproportionately affecting the poorest communities.

Comparison of Undernutrition and Overnutrition Causes


Cause	Undernutrition	Overnutrition
Dietary Intake	Insufficient calories, protein, and micronutrients.	Excessive intake of energy-dense foods high in fat and sugar.
Access to Food	Limited access due to poverty, conflict, or remote location.	Easy access to cheap, low-nutrient, high-calorie foods.
Lifestyle	Often linked to extreme poverty or chronic illness.	Associated with sedentary living and reduced physical activity.
Physiological Factors	Malabsorption disorders, infections, or increased metabolic demand.	Hormonal imbalances, metabolic slowdown (e.g., hypothyroidism).
Psychological Factors	Eating disorders like anorexia or mental health issues like dementia or depression.	Binge eating disorder, anxiety, or chronic stress.

The Devastating Impact on Child Development

The effects of malnutrition are particularly severe in children due to their rapid growth and development. Early-life malnutrition, especially during the critical first 1,000 days, can lead to irreversible physical and cognitive damage. This includes lower IQ scores, poor school performance, and delayed intellectual development. A child who is stunted or wasted will struggle to keep up with their peers, and their future earning potential and productivity as an adult may be significantly hampered. The long-term consequences of malnutrition also include a higher risk of chronic illnesses such as heart disease and diabetes in adulthood. Beyond the individual, the effects cripple economic prosperity and perpetuate cycles of poverty, making malnutrition not just a health issue but a developmental and societal one. For many, the consequences of malnutrition are a lifelong burden.

Conclusion

In its broadest sense, malnutrition can affect anyone, regardless of their location or economic status, though vulnerable groups are disproportionately impacted. The reasons are multifaceted, extending beyond just food availability to include socioeconomic status, education, public health infrastructure, and environmental factors. Addressing malnutrition requires a comprehensive, multi-sectoral approach that focuses on prevention, education, and empowering vulnerable communities with access to nutritious food and clean water. Combating this global challenge is a critical step toward achieving better health outcomes and sustainable development worldwide.

Frequently Asked Questions

Undernutrition is a deficiency of energy and nutrients, leading to wasting and stunting. Overnutrition is an excess intake of energy and nutrients, resulting in overweight and obesity.

Children are vulnerable due to their rapid growth and development, which requires a high intake of nutrients. Inadequate nutrition during the first 1,000 days of life can cause irreversible physical and mental damage.

No, malnutrition affects every country in some form. While undernutrition is more prevalent in low-income nations, overnutrition and micronutrient deficiencies are found globally, often coexisting.

Poverty is a significant driver because it limits access to and affordability of diverse, nutritious foods. Poor families may rely on cheaper, less nutritious, energy-dense foods, leading to deficiencies or overnutrition.

Long-term effects include stunted growth, reduced cognitive function, lower educational achievement, and an increased risk of chronic diseases in adulthood.

Yes. This is known as the 'double burden of malnutrition'. An overweight individual can consume an excess of calories but still lack essential vitamins and minerals, leading to micronutrient deficiencies.

Climate change and conflict disrupt food production and access, causing food shortages, rising prices, and displacement. These factors push already vulnerable populations deeper into food insecurity and malnutrition.