Why does kwashiorkor often develop after children are weaned from breast milk?

Kwashiorkor often develops after weaning because the child is transitioned from breast milk—which provides an adequate source of protein—to a diet consisting primarily of starchy, low-protein foods, such as cereal grains, cassava, plantains, or sweet potatoes.31

While the child may receive sufficient calories from these starchy carbohydrates, the lack of dietary protein leads to this specific form of malnutrition. The condition is frequently observed in young children between six months and five years of age, often coinciding with the arrival of a new sibling, which prompts the weaning process. Because the child's developing body requires protein for growth and maintenance, this sudden dietary shift leaves them vulnerable to the characteristic symptoms of the disease, including edema, weakness, and increased susceptibility to infectious diseases.213