Kwashiorkor is a form of severe malnutrition caused by not getting enough protein in the diet, even when calorie intake may be close to adequate. Its hallmark sign is bilateral pitting edema, a type of swelling that starts in the feet and legs and can spread to the hands, face, and belly. It primarily affects young children in regions where diets rely heavily on starchy foods with little protein, and it remains one of the two major forms of severe acute malnutrition worldwide, alongside marasmus.
How Kwashiorkor Differs From Marasmus
Severe acute malnutrition comes in two main forms, and they look very different. Marasmus results from an overall shortage of calories. Children with marasmus appear visibly emaciated: loose skin folds, sunken cheeks, visible ribs, and almost complete loss of body fat. Kwashiorkor, by contrast, is driven primarily by protein deficiency. A child with kwashiorkor may actually be getting enough calories from starchy foods like cassava, rice, or corn porridge, but almost none of those calories come from protein.
The visual difference is striking. A child with marasmus looks skeletal throughout the body. A child with kwashiorkor may look emaciated in the limbs but swollen in the hands, feet, face, and belly. That swelling is what distinguishes the two conditions and is so central to diagnosis that children with edema are automatically classified as having severe acute malnutrition, regardless of their weight or arm circumference measurements. A third category, marasmic kwashiorkor, combines features of both: severe wasting plus edema.
Why the Body Swells
The swelling in kwashiorkor traces back to a protein called albumin, which the liver produces and releases into the bloodstream. Albumin’s job is to maintain what’s called oncotic pressure, the force that keeps fluid inside blood vessels rather than leaking into surrounding tissues. When protein intake drops too low, the liver can’t produce enough albumin. Blood albumin levels fall, oncotic pressure drops, and fluid seeps out of the blood vessels into the tissues. The result is that characteristic puffiness, starting in the feet and lower legs and, in severe cases, spreading to the face and abdomen.
This is why kwashiorkor can be deceptive. The child’s weight may not look drastically low because the retained fluid masks the underlying muscle wasting. The swollen belly, sometimes called “moon face” when it affects the cheeks, can mislead caregivers into thinking the child is adequately nourished.
What Kwashiorkor Looks Like
Beyond the edema, kwashiorkor produces a constellation of visible changes across the skin, hair, and body. The skin develops what clinicians call “flaky paint” dermatosis: patches of darkened, dry, peeling skin, especially over pressure points or areas that experience friction. Sores often form at the corners of the mouth. The hair thins, becomes dry and brittle, and loses its natural pigment, sometimes turning reddish or straw-colored. Hair may fall out easily or can be pulled out with little resistance.
The liver often enlarges due to fatty buildup, a condition called hepatic steatosis. This happens because the liver needs protein to package and export the fats it processes. Without enough protein, fat accumulates in the liver cells instead of being transported out into the bloodstream. Children with kwashiorkor are also typically irritable, lethargic, and lose their appetite, which compounds the problem by making it harder to get them to eat.
What Causes It
Kwashiorkor most commonly develops in children between six months and five years old, often at the point when they transition from breastfeeding to solid foods. Breast milk provides a balanced mix of protein and calories, but in many low-resource settings, the weaning diet consists almost entirely of starchy gruels or porridges made from a single crop. These foods deliver energy but very little protein. The name “kwashiorkor” itself comes from a Ghanaian word roughly meaning “the disease the first child gets when the second child is born,” reflecting this transition away from breast milk.
Repeated infections play an amplifying role. Diarrheal diseases, measles, and parasitic infections increase the body’s protein demands while simultaneously reducing nutrient absorption from the gut. A child who might have survived on a marginal diet can tip into kwashiorkor after a bout of illness. Poverty, food insecurity, lack of dietary diversity, and limited access to animal-source foods like eggs, milk, or meat are the underlying drivers in nearly every case.
Dangerous Complications
Kwashiorkor suppresses the immune system, leaving children highly vulnerable to infections they would otherwise fight off. Bacterial infections of the skin, lungs, and bloodstream are common and can progress to sepsis. The body’s temperature regulation also breaks down, making hypothermia a real threat even in warm climates. Blood sugar can drop dangerously low because the body lacks the protein reserves to maintain glucose production between meals.
Electrolyte imbalances are another serious concern. Sodium and potassium levels shift in ways that can affect heart function. These complications are what make kwashiorkor fatal when untreated. A 15-year follow-up study of 221 infants hospitalized for kwashiorkor in the late 1950s found that 32% died from the malnutrition itself, either during their initial hospital stay or shortly after. Modern treatment protocols have improved survival significantly, but the condition remains deadly without intervention.
How It’s Treated
Treatment for kwashiorkor follows a carefully staged approach because reintroducing nutrients too quickly can overwhelm the body’s weakened systems. In the initial phase, children receive small, frequent feeds of a specially formulated therapeutic milk that provides modest calories and protein, about 75 calories and just under 1 gram of protein per 100 milliliters. This phase focuses on stabilizing the child: correcting low blood sugar, warming them if needed, treating infections, and carefully restoring electrolyte balance.
Once the child stabilizes (typically after a few days), feeds transition to a higher-protein formula providing 100 calories and about 3 grams of protein per 100 milliliters, with over half the energy coming from fat. This phase supports catch-up growth. Ready-to-use therapeutic foods, which are energy-dense pastes often made from peanuts, milk powder, sugar, and added vitamins, are also widely used, especially for outpatient treatment. The edema typically resolves within the first one to two weeks as albumin levels recover and the kidneys begin clearing the excess fluid.
Long-Term Outcomes for Survivors
Children who survive kwashiorkor can recover physically, but the context they return to matters enormously. The same 15-year follow-up study compared kwashiorkor survivors to their siblings who had never been malnourished but grew up in the same households. The survivors showed no significant differences in physical growth compared to their siblings. However, both groups demonstrated a pattern of stunted growth and delayed development compared to well-nourished children, reflecting the ongoing effects of poverty and food insecurity rather than kwashiorkor alone.
The critical finding was that severe malnutrition exacts most of its toll in the early years of life. Children who survived the acute episode and its immediate aftermath did not face elevated mortality in the years that followed. Still, emerging evidence links early severe malnutrition to lasting changes in gut health, immune function, and cognitive development, particularly when children experience malnutrition during the first 1,000 days of life, the window from conception to age two when brain development is most rapid.
Global Scale of the Problem
Kwashiorkor is not a relic of the past. Nutritional deficiencies in children accounted for roughly 577 million cases globally in 2021, though this figure encompasses all forms of malnutrition, not kwashiorkor alone. That total represents an 18% decline from 1990. Deaths from childhood nutritional deficiencies dropped even more dramatically, falling about 80% over the same period to roughly 84,000 deaths in 2021. The sharpest improvements came from better treatment protocols, wider availability of therapeutic foods, and community-based management programs that allow children to recover at home rather than in hospitals.
The burden is concentrated in sub-Saharan Africa and South Asia, where poverty, conflict, and limited healthcare infrastructure overlap. Projections suggest the death rate will continue declining through 2035, but the absolute number of children affected remains staggeringly high, and any disruption to food systems, whether from climate events, armed conflict, or economic collapse, can reverse gains quickly.