Which one is a common cause of undernutrition? A Look at Poverty, Disease, and Access

December 15, 2025 •

4 min read

Globally, nearly half of all deaths among children under five years of age are linked to undernutrition. The answer to which one is a common cause of undernutrition is multifaceted, involving a complex interplay of socioeconomic and health-related factors.

Quick Summary

This article examines the primary drivers of undernutrition, highlighting the vicious cycle of poverty and disease, inadequate dietary intake, and poor sanitation that contribute to this pervasive issue.

Key Points

Poverty is a leading cause: Financial limitations restrict access to nutritious foods, making poverty a fundamental driver of undernutrition globally.
Infectious diseases are a major contributor: The link between infection and undernutrition is a vicious cycle, where a weakened immune system leads to more disease, which in turn causes malabsorption and nutrient loss.
Malabsorption prevents nutrient uptake: Medical conditions like Crohn's disease, celiac disease, and severe diarrhea interfere with the body's ability to absorb nutrients, leading to deficiencies.
Poor sanitation exacerbates the problem: Inadequate hygiene and contaminated water sources are major causes of infectious diseases, particularly for children, contributing to malabsorption.
Certain life stages increase risk: Infants, children, pregnant women, and older adults are especially vulnerable due to heightened nutritional needs or physical limitations.
Education is a powerful tool: Promoting nutritional and health education, especially for mothers, can significantly improve a family's nutritional status and break the intergenerational cycle of malnutrition.

Poverty: The Most Common Underlying Cause

According to global health organizations like the WHO and World Bank, poverty is consistently identified as the leading and most pervasive common cause of undernutrition. This economic reality creates a cascade of other risk factors, perpetuating a cycle of ill-health and low productivity that is difficult to escape. In countries with high rates of food insecurity, undernutrition is widespread, affecting individuals' ability to access sufficient, safe, and nutritious food.

Food Insecurity and Lack of Access

Poverty directly translates to food insecurity, where individuals lack consistent access to an affordable and healthy food supply. While food is a major household expenditure for the poor, their limited and fluctuating incomes mean they often cannot afford nutritionally dense foods like fruits, vegetables, and protein sources. This leads to reliance on cheaper, high-energy staples, which can cause deficiencies in essential micronutrients, a condition known as "hidden hunger".

The Vicious Cycle of Infection and Malnutrition

Undernutrition is not just a result of poor diet; it is profoundly influenced by an individual's health status. A cycle of infection and undernutrition often forms, particularly in young children, where each condition exacerbates the other. An undernourished body has a weakened immune system, making it more susceptible to infectious diseases. Conversely, infections like persistent diarrhea can lead to a loss of appetite and nutrient malabsorption, worsening the undernourished state.

Impact of Poor Sanitation and Hygiene

Environmental factors such as poor sanitation and hygiene practices directly contribute to infectious diseases. Exposure to fecal bacteria through contaminated water or unhygienic food preparation can cause intestinal infections. Conditions like environmental enteropathy, prevalent in low-income settings, cause intestinal inflammation and damage, impairing the small intestine's ability to absorb nutrients effectively. The World Health Organization estimates that about 50% of all malnutrition is associated with repeated diarrhea or intestinal worm infections resulting from inadequate water, sanitation, and hygiene (WASH).

Medical and Other Contributing Conditions

Beyond the socioeconomic and environmental factors, a range of medical conditions can serve as a common cause of undernutrition, primarily by interfering with nutrient intake or absorption.

Malabsorption disorders: Conditions like Crohn's disease, celiac disease, or pancreatic insufficiency prevent the body from properly absorbing nutrients from food, even with a balanced diet.
Chronic illnesses: Diseases such as cancer, AIDS, and kidney failure can increase the body's nutrient requirements, reduce appetite, or alter metabolism, leading to undernutrition.
Mental health issues: Depression and dementia can significantly reduce an individual's appetite and motivation to eat, which is a major factor, especially among older adults.
Dental problems: Difficulty chewing or swallowing due to dental issues can restrict an individual's food choices and overall intake.

Vulnerable Groups and Life Stages

Certain populations are at a higher risk of undernutrition due to their specific needs and circumstances. These include:

Infants and Children: Growing bodies have very high energy and nutrient demands. Factors like poor maternal nutrition, inadequate breastfeeding, and insufficient complementary feeding can have irreversible effects, leading to stunting and wasting.
Pregnant and Lactating Women: Nutritional requirements increase dramatically during pregnancy and breastfeeding. Inadequate nutrition during these periods can harm both the mother and child, often resulting in low birth weight and long-term developmental issues for the baby.
Older Adults: Aging can bring a reduced appetite, decreased ability to absorb nutrients, reduced mobility for shopping or cooking, and loneliness, all of which increase the risk of undernutrition.

Comparing Social and Medical Causes of Undernutrition


Feature	Social/Economic Causes	Medical/Health Causes
Core Problem	Lack of access to affordable, nutritious food due to poverty.	Interference with the body's ability to consume, digest, or absorb nutrients.
Key Examples	Food insecurity, poor sanitation, lack of education, civil unrest.	Malabsorption disorders, chronic infections (diarrhea), cancer, dental issues, mental illness.
Impact Scope	Widespread community or national impact, affects vulnerable populations broadly.	Affects individuals regardless of wealth, but severity can be amplified by social factors.
Interventions	Social safety nets, economic development, public health education, WASH infrastructure.	Medical treatment, dietary modifications, nutritional supplementation, mental health support.
Cycle	Perpetuates a cycle of poverty and poor health across generations.	Creates a vicious cycle of illness and further nutrient depletion.

The Role of Education and Empowerment

Improving access to information about proper nutrition and hygiene is a critical step in combating undernutrition. Studies have shown that higher maternal education levels are significantly associated with better child nutritional outcomes. Educated parents are better equipped to make informed nutritional decisions for their children, practice proper hygiene, and seek out appropriate healthcare services.

Conclusion

Identifying which one is a common cause of undernutrition reveals that there is no single factor, but rather a complex web of interconnected issues. While poverty and its downstream effects like food insecurity are arguably the most fundamental and widespread causes, infectious diseases and underlying medical conditions play a significant role. Breaking the cycle requires a multi-pronged approach that addresses both the immediate health issues and the systemic social and economic drivers. Efforts to improve nutrition must therefore include promoting economic development, enhancing sanitation, expanding access to healthcare, and investing in education to empower individuals and communities toward better health outcomes. For more information, the World Health Organization offers extensive resources on the fight against malnutrition(https://www.who.int/news-room/fact-sheets/detail/malnutrition).

Frequently Asked Questions

Malnutrition is a broader term encompassing deficiencies, excesses, or imbalances in nutrient intake. Undernutrition is one form of malnutrition, specifically referring to a deficiency of calories or one or more essential nutrients.

Poverty causes undernutrition by limiting the ability to afford sufficient, nutritious food, leading to food insecurity. It also restricts access to clean water, sanitation, and healthcare, increasing the risk of infectious diseases that worsen nutritional status.

Yes, infectious diseases directly contribute to undernutrition. Conditions like chronic diarrhea can cause loss of appetite and prevent the body from absorbing nutrients, creating a vicious cycle of infection and malnutrition.

Malabsorption disorders prevent the small intestine from effectively absorbing nutrients from food into the bloodstream. This means that even if a person consumes a balanced diet, their body cannot utilize the nutrients, leading to deficiencies.

Children are vulnerable because of their high energy and nutrient demands for growth and development. Poor maternal nutrition, inadequate feeding practices, and repeated infections can severely impact their nutritional status during critical growth periods.

Good sanitation is crucial for preventing undernutrition, particularly in children. Poor sanitation can lead to a high incidence of intestinal infections and diarrhea, which impair nutrient absorption and contribute to chronic undernutrition.

Long-term effects of undernutrition can include stunting (impaired height-for-age), developmental delays, weakened immune systems, and increased risk of chronic diseases later in life, such as heart disease and diabetes.