Kwashiorkor and Marasmus: The Two Most Common Diseases That Result From Protein Deficiencies

October 19, 2025 •

4 min read

Worldwide, protein-energy malnutrition is a leading cause of mortality in children under the age of five. It manifests in two most common diseases that result from protein deficiencies: kwashiorkor and marasmus. These severe forms of malnutrition underscore the critical importance of a balanced diet, especially in vulnerable populations.

Quick Summary

This article details kwashiorkor and marasmus, the two main disorders stemming from severe protein-energy malnutrition. It covers their specific symptoms, underlying causes, distinguishing features, treatment protocols, and preventative measures.

Key Points

Two Common Protein Deficiency Diseases: Kwashiorkor, defined by edema, and marasmus, characterized by severe wasting, are the most common severe disorders resulting from protein and calorie deficiencies.
Kwashiorkor Symptoms: Look for swelling, a distended belly, and changes to skin and hair. The edema can hide severe underlying malnutrition.
Marasmus Symptoms: Characterized by extreme emaciation, loss of fat and muscle mass, and a 'skin and bones' appearance with no edema.
Key Difference: Kwashiorkor involves a primary protein lack, often with sufficient calories, while marasmus is a deficiency of all major nutrients.
Treatment Focus: Treatment requires careful dietary rehabilitation, starting with stabilization of metabolic issues before gradually reintroducing nutrient-dense foods.
Prevention is Key: Ensuring access to a varied, protein-rich diet is the best prevention. Educational programs and addressing poverty are crucial.
Vulnerable Populations: Children, pregnant women, and the elderly in areas of food scarcity are most at risk, though other medical conditions can also cause these diseases.

Understanding Protein-Energy Malnutrition

Protein is a vital macronutrient essential for almost every bodily function, from building and repairing tissues to producing enzymes and hormones. When the body is deprived of adequate protein, particularly alongside insufficient calorie intake, it can lead to a state known as Protein-Energy Malnutrition (PEM). The most severe forms of PEM present as two distinct and life-threatening conditions: kwashiorkor and marasmus. While both are rooted in nutritional deficiencies, their clinical manifestations and underlying physiological responses to starvation differ significantly. Kwashiorkor primarily results from a severe lack of protein, while marasmus is a deficiency of all macronutrients—protein, carbohydrates, and fats. These diseases predominantly affect children in developing regions due to food insecurity, poverty, and lack of access to nutritious foods.

Kwashiorkor: The Swollen Malnutrition

The term 'kwashiorkor' comes from the Ga language of Ghana and means "the sickness the baby gets when the new baby arrives," referring to the time when an older child is weaned from protein-rich breast milk and given a carb-heavy diet. The defining symptom of kwashiorkor is edema, a fluid retention that causes swelling, especially in the hands, feet, and face. This swelling can mask the underlying emaciation. The characteristic swollen belly, a sign of ascites (fluid accumulation in the abdominal cavity) and an enlarged fatty liver, is also a classic sign.

Common symptoms of Kwashiorkor include:

Edema: Swelling, particularly in the ankles, feet, and abdomen.
Enlarged fatty liver: Impaired liver function leads to fat accumulation in liver cells.
Skin and hair changes: Skin lesions, dryness, and patches of depigmented skin, along with brittle, sparse hair that may lose its color.
Apathy and irritability: Behavioral changes are common in affected children.
Impaired immune response: A weakened immune system makes individuals more susceptible to infections.
Stunted growth: Both physical and intellectual development can be significantly delayed.

Marasmus: The Wasting Malnutrition

Marasmus, derived from the Greek word meaning "starvation," represents a severe deficiency of both protein and calories. Unlike kwashiorkor, marasmus is characterized by profound wasting of fat and muscle tissue, leading to a severely emaciated, "skin and bones" appearance with prominent ribs and loose, hanging skin. The body's adaptive response to starvation involves breaking down its own muscle and fat to provide energy.

Common symptoms of Marasmus include:

Severe muscle and fat wasting: A gaunt, extremely underweight appearance is the most obvious sign.
Failure to thrive: In infants, there is a clear failure to gain weight and grow normally.
Extreme weakness: Sufferers experience acute fatigue and lethargy.
Monkey facies: A wrinkled, aged face appearance due to the loss of buccal fat pads.
Subdued appetite: In some cases, marasmus can ironically lead to food aversion.
Anemia: Low iron levels are common in severely malnourished individuals.

Kwashiorkor vs. Marasmus: A Comparative Look

The following table highlights the key differences between these two common protein deficiency diseases:


Feature	Kwashiorkor	Marasmus
Primary Deficiency	Predominantly protein deficiency, with often adequate calorie intake.	Overall calorie and macronutrient deficiency (protein, fat, carbs).
Appearance	May not appear extremely thin due to edema (swelling).	Appears severely emaciated with pronounced muscle and fat wasting.
Edema (Swelling)	Present and is a classic distinguishing feature.	Absent, leading to a wasted, 'skin and bones' appearance.
Fatty Liver	Enlarged, fatty liver is a common symptom.	Fatty liver is typically not present.
Subcutaneous Fat	Often preserved, which can be misleading.	Almost completely lost, resulting in loose skin folds.
Appetite	Poor or loss of appetite is typical.	Can range from being present to subdued or averse to food.

Treatment and Prevention

Treating kwashiorkor and marasmus requires a two-phase approach under medical supervision. The initial phase focuses on stabilizing the patient, addressing immediate health threats like electrolyte imbalances, dehydration, infection, and low body temperature. The second phase, rehabilitation, involves slowly reintroducing nutrient-dense, high-protein foods to restore nutritional status and encourage weight gain and growth. A personalized dietary plan is crucial to avoid refeeding syndrome, a potentially fatal shift in fluids and electrolytes.

Preventing these diseases is far more effective than treating them. Strategies include improving access to a diverse range of high-quality protein foods, particularly for vulnerable populations like children and pregnant women. Educating communities on proper nutrition, promoting breastfeeding, and addressing underlying issues like poverty and food insecurity are also vital steps. For individuals in developed countries, protein deficiency can often be a consequence of underlying medical conditions such as eating disorders, malabsorption issues, or advanced stages of cancer. In these cases, treatment involves addressing the root cause alongside dietary modifications.

Conclusion

Kwashiorkor and marasmus are severe conditions resulting from protein deficiencies, each with a distinct clinical presentation. While kwashiorkor is characterized by edema from insufficient protein despite caloric intake, marasmus is marked by profound wasting due to a complete caloric and protein deficit. Both can have devastating and long-term health consequences, especially for children, including stunted growth, impaired immunity, and potential organ failure. Early diagnosis, careful medical treatment, and comprehensive nutritional rehabilitation are critical for recovery. Ultimately, prevention through access to a consistent, nutrient-rich diet remains the most powerful tool against these debilitating forms of malnutrition. For more information on dietary guidelines for adequate protein intake, consult the recommendations from health authorities like the Harvard T.H. Chan School of Public Health: https://nutritionsource.hsph.harvard.edu/what-should-you-eat/protein/.

Frequently Asked Questions

Kwashiorkor is primarily a protein deficiency, characterized by edema (swelling) even if calorie intake is sufficient. Marasmus is a deficiency of all macronutrients, including protein and calories, resulting in severe wasting and emaciation without swelling.

While these diseases are most common in children in developing countries, adults can also develop them under extreme starvation or due to chronic illnesses, eating disorders, or malabsorption issues.

Diagnosis typically involves a physical examination for symptoms like edema or muscle wasting, a dietary assessment, and blood tests to check for low protein levels (hypoproteinemia) and other nutritional markers.

Causes include insufficient dietary intake of protein-rich foods, malabsorption syndromes (e.g., Crohn's disease), increased protein demand during pregnancy or illness, and poverty leading to food insecurity.

Treatment involves medical supervision to correct metabolic issues and infections first. This is followed by gradual refeeding with nutrient-dense foods, vitamin and mineral supplements, and a long-term rehabilitation plan.

Yes, with proper dietary adjustments and medical care, protein deficiency can be reversed. Early intervention is crucial to prevent long-term complications such as stunted growth and impaired organ function.

Excellent sources include lean meats, fish, eggs, dairy products, legumes (beans, lentils), nuts, and seeds. A variety of these foods should be consumed to get all essential amino acids.