Understanding the Nutrition Diet: What are the two diseases caused by protein?

October 6, 2025 •

4 min read

According to UNICEF, undernutrition contributes to at least one-third of deaths in young children worldwide. The most severe forms of protein-energy malnutrition are Kwashiorkor and Marasmus, which are the two diseases caused by protein deficiency and a lack of overall calories. Understanding these life-threatening conditions is crucial for preventing and treating severe nutritional deficits.

Quick Summary

Kwashiorkor and Marasmus are the two primary diseases resulting from severe protein-energy malnutrition. Kwashiorkor is characterized by a protein deficiency leading to edema, while Marasmus is a severe wasting disease caused by an overall lack of calories and protein, resulting in emaciation.

Key Points

Kwashiorkor Causes Edema: This condition is characterized by a severe protein deficiency despite some caloric intake, leading to fluid retention and swelling, especially in the abdomen and limbs.
Marasmus Causes Wasting: Marasmus results from a severe deficiency of both protein and calories, causing dramatic muscle and fat loss and a shriveled, emaciated appearance.
Distinct Age Groups: Kwashiorkor typically affects toddlers (1-3 years old) after weaning, whereas Marasmus often affects infants under one year due to inadequate feeding.
Metabolic Differences: The body’s adaptation to nutrient deprivation differs; in Marasmus, fat and muscle stores are burned, while in Kwashiorkor, metabolic and immune functions are significantly impaired.
Treatment is Gradual: The medical treatment for both conditions involves careful, gradual refeeding under supervision to prevent complications like refeeding syndrome.
Prevention is Key: Access to a balanced, nutrient-rich diet and public health measures focusing on education and disease control are vital for preventing both diseases.

Protein is a macronutrient vital for virtually every function in the human body, including cell repair, new cell creation, immune system function, and growth. When the body is deprived of sufficient protein, it can lead to severe health consequences. While less common in developed nations, severe protein-energy malnutrition (PEM) is a leading cause of death for children in low-income countries. The two most well-known and severe diseases associated with inadequate protein intake are Kwashiorkor and Marasmus.

What are the two diseases caused by protein? Kwashiorkor and Marasmus

Kwashiorkor: The 'Sickness of the Displaced Child'

The term "Kwashiorkor" comes from a Ghanaian language and translates to "the sickness the child gets when the new baby comes". This name describes the typical scenario where the disease occurs in an older child, often between ages 1 and 3, who is weaned from protein-rich breast milk and given a carbohydrate-heavy, low-protein diet.

Common causes of Kwashiorkor include:

Dietary Imbalance: A diet consisting mainly of starchy foods like rice, maize, or cassava with very little protein.
Sudden Weaning: The abrupt transition from breastfeeding to an inadequate diet.
Infections: Illnesses such as diarrhea and measles, which can increase the body's nutrient needs and impair absorption.

Distinct symptoms of Kwashiorkor include:

Edema: A hallmark sign is swelling due to fluid retention, particularly in the ankles, feet, hands, and face.
Distended Belly: The abdomen often appears bloated or protuberant, which can mask the underlying malnutrition.
Hair and Skin Changes: Hair may become dry, brittle, and discolored, sometimes acquiring a reddish or yellowish tone. Skin can develop a "flaky paint" rash and be dry and peeling.
Fatty Liver: An enlarged, fatty liver is a common symptom.
Behavioral Changes: Children often exhibit apathy, irritability, and a loss of appetite.

Marasmus: The ‘Wasting’ Disease

Marasmus, a Greek word meaning "withering," results from a severe deficiency of all macronutrients—protein, carbohydrates, and fats. It is a form of severe protein-energy malnutrition characterized by a severe lack of calories, not just protein. Marasmus most commonly affects infants, typically under the age of one.

Common causes of Marasmus include:

Calorie and Protein Deficiency: A consistent lack of food, leading to a general energy deficit.
Inadequate Breastfeeding: Improper or insufficient breastfeeding, especially if the mother is also malnourished.
Chronic Illness: Conditions like chronic diarrhea, infectious diseases, or illnesses like HIV/AIDS can contribute to wasting.

Distinct symptoms of Marasmus include:

Severe Wasting: A drastic loss of muscle mass and subcutaneous fat, giving the person a shrunken, emaciated appearance.
Visible Ribs and Joints: The extreme lack of fat and muscle leaves the bones prominently visible.
Loose, Wrinkled Skin: The skin hangs in loose folds due to the absence of underlying fat.
Stunted Growth: Significant delays in growth and development are common in children.
Aged Appearance: The loss of facial fat can make an infant or child look older than their age.

Comparing Kwashiorkor and Marasmus


Distinguishing Factor	Kwashiorkor	Marasmus
Primary Deficiency	Primarily protein deficiency, with relatively adequate caloric intake.	Deficiency of both protein and total calories.
Edema (Swelling)	Present and is a defining feature, often in the feet, ankles, and abdomen.	Absent, leading to a very shriveled and wasted look.
Subcutaneous Fat	Some body fat is retained, masked by edema.	Severely depleted, giving a "skin and bones" appearance.
Weight Loss	Moderate weight loss; edema can mask the true extent of weight loss.	Severe weight loss, with weight-for-age being significantly low.
Fatty Liver	Enlarged, fatty liver is a common clinical feature.	Not a common feature; the liver is reduced in size.
Affected Age Group	Often seen in children aged 1–3 years, post-weaning.	Most common in infants under 1 year of age.
Appetite	Poor appetite and apathy are common.	Variable appetite, but often poor.
Skin and Hair	Changes in skin pigmentation, dry flaky rash, and hair discoloration.	Dry, wrinkled skin and brittle hair, but less pronounced discoloration.

Prevention and Treatment for Protein-Energy Malnutrition

Prevention is the most effective strategy against these severe forms of malnutrition, and it centers on ensuring access to adequate and balanced nutrition. This includes educating caregivers on proper feeding practices and providing access to a variety of protein and calorie sources. In areas of high risk, public health initiatives focus on nutritional support programs, disease control (including vaccination), and improving sanitation to prevent infectious diseases that worsen malnutrition.

Treatment for Kwashiorkor and Marasmus is a serious and delicate process, ideally performed under medical supervision to avoid life-threatening complications like refeeding syndrome. The World Health Organization (WHO) outlines a phased approach:

Stabilization: The initial stage focuses on treating immediate life-threatening issues such as dehydration, infections, electrolyte imbalances, and hypothermia. This often involves specialized rehydration solutions and antibiotics.
Rehabilitation: Once stable, feeding is reintroduced cautiously, starting with small, frequent meals of therapeutic formulas that balance nutrients. For children, the goal is often accelerated "catch-up growth".
Follow-up: Long-term follow-up and continued nutritional support are essential to prevent relapse. Education for caregivers is a critical part of this stage.

Conclusion

Kwashiorkor and Marasmus represent the most severe manifestations of protein-energy malnutrition, each with distinct features driven by different underlying nutritional deficiencies. While Kwashiorkor is predominantly a protein deficiency marked by edema, Marasmus is a total calorie and protein deficit resulting in severe wasting. Both conditions disproportionately affect young children in impoverished areas but can be caused by underlying health conditions even in developed countries. The successful prevention and treatment of these diseases rely on a comprehensive approach involving proper nutrition, sanitation, disease control, and careful medical management.

For more detailed medical information, consider consulting resources such as the Cleveland Clinic's page on Kwashiorkor: https://my.clevelandclinic.org/health/diseases/23099-kwashiorkor.

Frequently Asked Questions

The primary difference is the type of nutrient deficiency. Kwashiorkor is mainly a severe protein deficiency, while Marasmus is a severe deficiency of both protein and total calories.

The swelling, known as edema, occurs due to the low levels of protein, particularly albumin, in the blood. Albumin helps maintain fluid balance; without enough of it, fluid leaks into the tissues.

An infant with Marasmus appears visibly wasted and emaciated. They lose significant muscle mass and subcutaneous fat, which leaves them looking shriveled with prominent ribs and loose, wrinkled skin.

Yes, a condition known as Marasmic Kwashiorkor exists, which presents with symptoms of both diseases, including both severe wasting and edema.

If left untreated, both Kwashiorkor and Marasmus can be fatal. They can lead to severe infections, permanent developmental and physical disabilities, and organ failure.

While severe Kwashiorkor and Marasmus are rare in developed countries, protein deficiency can still occur due to eating disorders, fad diets, or other underlying medical conditions.

Treatment begins slowly and cautiously with medical supervision to correct life-threatening conditions like dehydration and electrolyte imbalances, before gradually reintroducing nutrients.

Even with successful treatment, survivors may experience long-term effects, such as stunted growth, intellectual disabilities, and increased susceptibility to chronic health issues later in life.