Who is most affected by kwashiorkor?: A Deep Dive into High-Risk Populations

October 26, 2025 •

5 min read

According to UNICEF, nearly half of all child deaths under the age of five are linked to undernutrition, with severe conditions like kwashiorkor playing a significant role. This form of malnutrition, primarily caused by a severe protein deficiency, most often affects young children, but a combination of factors determines who is most affected by kwashiorkor.

Quick Summary

Kwashiorkor, a form of severe protein malnutrition, predominantly affects children aged 1-5 years in developing regions with food insecurity and monotonous, carbohydrate-heavy diets. Vulnerable populations include recently weaned infants, those in poverty, and individuals with underlying infections like measles or HIV.

Key Points

Young children are most affected: The highest prevalence of kwashiorkor is among children aged 1 to 5, particularly after being weaned from breast milk onto low-protein diets.
Geography is a key factor: It is most common in developing regions with high poverty and food insecurity, including sub-Saharan Africa, Central America, and Southeast Asia.
Infections increase risk: Infectious diseases such as measles, diarrhea, and HIV increase the body's nutritional demands and worsen malnutrition.
Dietary monotony is a trigger: A diet rich in carbohydrates (like maize or cassava) but lacking protein and micronutrients is a primary risk factor.
Socioeconomic status matters: Poverty, famine, and limited access to health education are significant drivers of kwashiorkor.
Kwashiorkor is distinct from marasmus: Kwashiorkor is characterized by edema (swelling) from protein deficiency, unlike the severe wasting of marasmus caused by overall caloric deprivation.
Prevention is possible: Multi-faceted public health strategies involving nutrition education, improved food security, and disease control can prevent kwashiorkor.

Kwashiorkor is a severe form of protein-energy malnutrition characterized by fluid retention (edema) and a distended abdomen. While a general lack of protein is the central cause, a complex mix of socioeconomic, environmental, and physiological factors identifies who is most affected by this devastating condition. The condition is relatively rare in developed countries but remains a significant public health issue in resource-limited settings globally.

The Primary Demographics: Young Children in Developing Nations

At the forefront of the populations most affected by kwashiorkor are young children, particularly those aged between one and five years old. The name itself, from the Ga language of Ghana, means “the sickness the baby gets when the new baby comes,” directly referencing a common scenario that triggers the condition. This is when an older toddler is weaned from nutrient-rich breast milk and replaced with a less adequate diet to allow a new sibling to be breastfed. Their immature digestive and immune systems make them especially susceptible to the impacts of a low-protein diet.

Geographical Concentration

Kwashiorkor is predominantly seen in developing countries where food insecurity and poverty are widespread. Regions with a high prevalence of cases include:

Sub-Saharan Africa: Widespread poverty and dependence on carbohydrate staples like maize and cassava contribute significantly to malnutrition.
Southeast Asia: Similar economic and dietary factors, often worsened by natural disasters, lead to higher rates of kwashiorkor.
Central America and the Caribbean: Poverty and reliance on specific regional staples can also result in protein-deficient diets. Rural and farming communities within these regions are often the hardest hit, as they may have less access to diverse protein sources.

Factors Compounding the Risk of Kwashiorkor

While age and location are major indicators, several other risk factors exacerbate the likelihood of developing kwashiorkor in vulnerable populations.

Inadequate Weaning Practices: The transition from breast milk to a diet high in carbohydrates but low in protein is a critical trigger. In areas where protein-rich foods like meat, fish, and legumes are scarce or expensive, young children are often given starchy porridges and gruels that do not meet their nutritional needs.
Infections and Disease: Frequent or chronic infections, including measles, malaria, and diarrhea, can precipitate or worsen kwashiorkor. Infections increase the body’s nutritional demands and can cause appetite loss, malabsorption, and significant nutrient loss, depleting the body’s already limited protein stores. Conditions like HIV and tuberculosis also increase susceptibility.
Poor Sanitation and Hygiene: Unhygienic living conditions can contribute to repeated infections, creating a vicious cycle that depletes the body's resources and further compromises the immune system.
Food Contamination: The presence of mycotoxins like aflatoxins, which can grow on staple crops in hot, humid climates, has been implicated in the development of kwashiorkor. Aflatoxin exposure is linked to liver damage and can worsen the effects of protein deficiency.
Socioeconomic Factors: Famine, political instability, and extreme poverty remain key drivers. During famines or conflicts, food scarcity can lead to an over-reliance on whatever calories are available, often without sufficient protein. Lack of nutritional education also plays a significant role in perpetuating the condition.

The Rare Cases in Developed Nations

Kwashiorkor is an almost unheard-of condition in countries with robust food supplies and healthcare systems. However, cases can arise due to specific circumstances:

Child or Elder Abuse and Neglect: In severe cases of neglect, individuals may be deprived of a balanced diet, leading to kwashiorkor.
Underlying Chronic Illnesses: Certain medical conditions can impair nutrient absorption or increase metabolic demand. This can include gastrointestinal disorders, cancer, or HIV/AIDS.
Severely Restricted Fad Diets: Parents who impose extremely restrictive, low-protein diets on their children due to unverified concerns about food allergies, for example, have also been linked to cases of kwashiorkor.

Kwashiorkor vs. Marasmus: A Key Distinction

While both fall under the umbrella of severe acute malnutrition (SAM), they manifest differently due to the nature of the dietary deficiency. Kwashiorkor is often an acute condition triggered by a lack of protein, while marasmus is a more chronic condition resulting from a deficiency of both protein and calories.


Feature	Kwashiorkor	Marasmus
Primary Deficiency	Protein deficiency, with potentially adequate calorie intake.	Deficiency of both protein and calories.
Edema (Swelling)	Present and is a key diagnostic feature, especially in the abdomen, feet, and ankles.	Absent.
Body Appearance	Swollen extremities and belly, but may retain some subcutaneous fat.	Severe wasting and emaciation, with visible bone structure.
Fatty Liver	Enlarged, fatty liver is common.	Not typically affected.
Weaning	Often triggered by weaning onto a starchy diet.	Typically affects infants earlier in life due to overall starvation.

Prevention and Intervention Strategies

Preventing kwashiorkor requires a multifaceted approach that tackles the root causes of food insecurity, poor health, and a lack of nutritional education. Public health initiatives are crucial in high-risk areas. The World Health Organization (WHO) outlines a 10-step approach for managing severe undernutrition, starting with cautious refeeding to avoid refeeding syndrome. Education and access to resources are paramount for long-term prevention.

Educating caregivers about proper infant and child nutrition, promoting breastfeeding, and supporting agricultural practices that provide diverse, protein-rich foods are all critical. Improved sanitation and vaccination programs can also help reduce the burden of infections that contribute to malnutrition. International efforts by organizations like the WHO and UNICEF, along with local healthcare providers, are essential for implementing effective prevention and treatment strategies. Early intervention, starting with therapeutic foods and close monitoring, can reverse the effects of kwashiorkor and prevent long-term physical and mental disabilities.

For more information on global malnutrition prevention efforts, visit the World Health Organization's website.

Conclusion

While primarily known as a devastating affliction of young children in impoverished regions, the question of who is most affected by kwashiorkor reveals a complex web of interwoven factors. From the precarious period of weaning in developing nations to rare cases linked to neglect or illness in developed countries, kwashiorkor highlights deep-seated issues of food security, sanitation, and health access. Understanding the specific populations at risk and the combined effect of protein deficiency with factors like infection and poverty is crucial for effective prevention and treatment. Timely intervention can mitigate the severe long-term consequences and pave the way for a healthier future for at-risk children worldwide.

Frequently Asked Questions

Kwashiorkor most commonly affects children between the ages of one and five, particularly during or after the weaning period when they transition from breast milk to solid foods.

While it predominantly affects children, kwashiorkor can occur in adults, though it is less common. In developed countries, cases in adults are often linked to chronic illness, substance abuse, or severe neglect.

When an infant is weaned from breast milk, they are often transitioned to a diet primarily composed of high-carbohydrate, low-protein foods like starchy porridges. This sudden lack of protein can trigger the condition.

Yes, but it is very rare. When it does, it is typically a sign of severe neglect, child abuse, or underlying medical conditions that affect nutrient absorption.

Infections like measles, diarrhea, and HIV increase the body's need for nutrients and can interfere with their absorption. This, combined with an already protein-deficient diet, can precipitate or worsen kwashiorkor.

If left untreated or treated too late, kwashiorkor can lead to permanent physical and mental disabilities, stunted growth, weakened immunity, and, in severe cases, shock, coma, and death.

No, they are different forms of severe malnutrition. Kwashiorkor is characterized by edema (swelling) due to severe protein deficiency, while marasmus is a wasting syndrome caused by a severe deficiency of both protein and calories.