What are two common diseases that result from protein deficiencies? An In-depth Look at Malnutrition

October 4, 2025 •

4 min read

According to the World Health Organization, protein-energy malnutrition contributes to an estimated 45% of child deaths annually in developing countries. Severe and prolonged dietary protein insufficiency can lead to life-threatening conditions, but what are two common diseases that result from protein deficiencies? The two most widely recognized are Kwashiorkor and Marasmus, distinct forms of severe malnutrition with serious health implications.

Quick Summary

The most common and severe diseases caused by a lack of protein are Kwashiorkor and Marasmus, both forms of protein-energy malnutrition (PEM). Kwashiorkor results primarily from a protein deficit, causing fluid retention and a swollen abdomen, while Marasmus is due to a severe deficiency of all macronutrients, leading to extreme weight loss and muscle wasting.

Key Points

Kwashiorkor: A disease caused by severe protein deficiency, characterized by fluid retention, a swollen abdomen, and skin and hair discoloration, despite relatively adequate caloric intake.
Marasmus: Caused by a severe and chronic deficiency of both calories and protein, leading to extreme weight loss, muscle wasting, and a starved appearance.
Visible Differences: Kwashiorkor is defined by edema (swelling), while Marasmus is defined by emaciation (wasting).
Underlying Causes: Both conditions are prevalent in impoverished regions with food scarcity, often exacerbated by infections and poor hygiene.
Crucial Treatment: Early and cautious refeeding is critical for both conditions to prevent life-threatening complications like refeeding syndrome and to improve long-term outcomes.
Prevention Focus: Prevention relies on improving access to nutritious food, especially high-quality protein sources, and providing education on proper dietary practices.

Kwashiorkor: Edematous Malnutrition

Kwashiorkor, often called 'edematous malnutrition' due to its characteristic swelling, is primarily a result of a severe protein deficiency, even when the overall caloric intake is adequate but lacks sufficient protein. The name, which comes from the Ga language of Ghana, translates to 'the sickness the baby gets when the new baby comes,' referring to the condition that often affects a weaned child when a new sibling is born. The child's diet shifts from protein-rich breast milk to low-protein, carbohydrate-heavy foods like starchy vegetables or grains, triggering the onset of the disease.

Symptoms of Kwashiorkor

Edema: Swelling caused by fluid retention, particularly in the ankles, feet, hands, and face.
Distended abdomen: The characteristic 'potbelly' appearance is due to fluid accumulation (ascites) and a fatty liver.
Skin and hair changes: Skin can become dry, scaly, and develop rashes or peeling patches, resembling 'flaky paint.' Hair may become dry, brittle, lose its color, or fall out easily.
Muscle wasting: Despite the swollen appearance, there is a significant loss of muscle mass.
Fatigue and irritability: Children often display lethargy, apathy, and irritability.

Causes and Complications of Kwashiorkor

While insufficient protein is the core issue, other factors exacerbate the condition, including poor sanitation leading to frequent infections, which further deplete the body's resources and compromise the immune system. Without treatment, Kwashiorkor can lead to severe complications such as shock, liver failure, permanent intellectual and physical disabilities, and ultimately, death.

Marasmus: Wasting Malnutrition

Marasmus, derived from the Greek word 'marasmos' meaning 'withering,' is a form of severe protein-energy malnutrition (PEM) caused by a chronic, severe deficiency of all macronutrients: protein, carbohydrates, and fats. This is essentially severe starvation, where the body breaks down its own fat and muscle tissues to use as energy to sustain vital functions. Marasmus typically affects infants and very young children, especially in regions of famine and extreme poverty, or in cases of severe neglect.

Symptoms of Marasmus

Extreme weight loss: The most visible sign is severe weight loss and a starved, emaciated appearance, often with bones protruding through the skin.
Wasting: The body wastes away muscle and subcutaneous fat stores, causing the face to appear old and wizened, and the skin to be loose and wrinkled.
Lethargy and weakness: Children with Marasmus are often extremely weak, inactive, and apathetic.
Growth retardation: Stunted physical growth and developmental delays are common.
No edema: Unlike Kwashiorkor, swelling is absent in Marasmus, as there is no fluid retention.

Causes and Complications of Marasmus

The primary cause is inadequate food intake due to circumstances like poverty, food shortages, and infectious diseases that increase metabolic demand or decrease appetite. Complications include a compromised immune system, dehydration, hypothermia, electrolyte imbalances, and heart failure. The prognosis is more dire the longer the condition goes untreated, with prolonged cases leading to permanent cognitive impairment.

A Comparison of Kwashiorkor and Marasmus

To distinguish between these two serious conditions, a comparison is helpful. It's important to remember that some individuals may suffer from a combination of both, known as Marasmic Kwashiorkor.


Feature	Kwashiorkor	Marasmus
Primary Deficiency	Protein, with adequate or near-adequate calorie intake.	Calories and all macronutrients (protein, fat, carbohydrates).
Physical Appearance	Swollen abdomen and extremities (edema), 'moon face,' while limbs may look thin.	Wasted, emaciated, and shriveled appearance; 'old man face' due to loss of fat.
Key Symptom	Edema is the defining characteristic.	Extreme muscle and fat wasting is the defining characteristic.
Commonly Affected Age	Toddlers, especially after weaning (1-3 years).	Infants and very young children (<1 year).
Liver Condition	Fatty liver is a frequent finding.	Normal or reduced-size liver.
Immune Response	Significantly impaired, increasing susceptibility to infections.	Also impaired, though potentially less so than in Kwashiorkor.

Prevention and Treatment

Prevention is the most effective strategy against these debilitating diseases. It involves ensuring access to a balanced, protein-rich diet, particularly for vulnerable populations like children and the elderly. Education on proper nutrition, hygiene, and safe weaning practices is crucial in at-risk communities. Public health programs, food security initiatives, and addressing underlying issues like poverty and infectious disease are vital steps in prevention.

For those affected, treatment is a carefully managed process. The World Health Organization outlines a step-by-step rehabilitation plan, beginning with stabilizing the patient and treating immediate life-threatening issues like hypoglycemia, hypothermia, and infection. Rehydration with special solutions like ReSoMal is administered cautiously to correct electrolyte imbalances. Nutritional rehabilitation follows, with a slow, incremental reintroduction of calories and protein to prevent a dangerous condition called refeeding syndrome. Nutritional support, vitamin and mineral supplements, and ongoing medical supervision are critical for recovery. Early and consistent intervention is essential to maximize the chances of a positive outcome and minimize long-term developmental and health issues.

Conclusion

Kwashiorkor and Marasmus are devastating but preventable conditions resulting from insufficient dietary protein. While one is characterized by severe protein deficiency leading to edema and the other by overall macronutrient starvation leading to wasting, both highlight the critical role of adequate nutrition for healthy growth and development. Global efforts toward improving food security, nutritional education, and healthcare access are essential to combatting these diseases and saving countless lives. Awareness and early intervention are key to successfully treating those affected and minimizing the long-term consequences of these severe protein deficiencies.

Frequently Asked Questions

The primary cause of Kwashiorkor is a severe deficiency of protein in the diet, which most commonly occurs in children who are weaned from protein-rich breast milk and are then given a carbohydrate-heavy, low-protein diet.

The defining difference is the presence of edema, or swelling, in Kwashiorkor, which is caused by fluid retention due to low protein levels. In contrast, Marasmus is characterized by severe, visible muscle and fat wasting without edema.

While Kwashiorkor and Marasmus primarily affect children, adults can also develop these conditions, particularly if they have chronic illnesses, eating disorders like anorexia, or are elderly and suffering from neglect or a very poor diet.

Common risk factors include poverty, food insecurity, lack of nutritional education, limited access to varied and healthy foods, chronic illness, and infectious diseases.

Treatment involves a carefully managed process starting with stabilizing the patient and treating dehydration, infections, and electrolyte imbalances. Following stabilization, a cautious nutritional rehabilitation plan is implemented with incremental refeeding to prevent complications.

Long-term effects can include permanent stunting of growth, intellectual and cognitive impairment, and persistent organ damage, particularly to the liver. The earlier the treatment, the better the prognosis.

Rapidly refeeding a severely malnourished person can lead to a potentially fatal condition called refeeding syndrome. This syndrome causes dangerous shifts in fluid and electrolyte levels, which can lead to cardiac and respiratory failure.