Nutritional Deficiency and Health Disorders
Senior 3 · Home Science
Nutritional Deficiency and Health Disorders
Lesson 1 of 4
24 min
Let's begin
In 2025, about 27 children in every 100 under the age of five in Rwanda were stunted: too short for their age because they had not had enough good food, or had been ill too often, for a long time. That is a real improvement on 33 in every 100 in 2019–20, but it still means more than one child in four. Stunting is hard to reverse after the age of two, and it affects learning as well as height. At its most severe, poor feeding leads to two dangerous conditions you must be able to recognise and prevent: kwashiorkor and marasmus.
Definition
Malnutrition: poor nutrition from eating too little, too much or the wrong balance of nutrients. It includes undernutrition, deficiencies of vitamins and minerals, and overweight.
Protein-energy malnutrition (PEM): undernutrition caused by too little energy (calories) and protein, often together with infection.
Stunting: low height for age, a sign of long-term undernutrition. Wasting: low weight for height, a sign of recent, severe weight loss.
Oedema: swelling caused by fluid collecting in the body's tissues, first seen in the feet and lower legs.
| Feature | Kwashiorkor | Marasmus |
|---|---|---|
| Main cause | diet low in protein, often while still getting some starchy food, usually after an infection | severe lack of energy and of all nutrients: starvation |
| Usual age | 1 to 3 years, often after weaning from the breast | under 1 year, or any age in famine |
| Swelling (oedema) | yes: feet, legs, then face ("moon face") | no |
| Body | muscles wasted but hidden by swelling; swollen belly from a fatty liver | "skin and bones": no fat, loose skin folds, ribs showing, an old-looking face |
| Hair and skin | thin hair that loses its colour and pulls out easily; dark, peeling patches of skin | dry, thin skin; hair thin but less changed |
| Mood and appetite | miserable, apathetic, poor appetite | often alert and hungry |
Kwashiorkor used to be explained simply as "too little protein". Doctors now know that infections and other factors also play a part, and that many children show signs of both conditions (marasmic kwashiorkor). Both are severe acute malnutrition, an emergency that must be treated at a health centre. There, children are given special therapeutic foods in small, frequent feeds; suddenly giving a very ill child large meals at home can be dangerous.
For one child's serving: 2 level tablespoons of maize or sorghum flour, 1 tablespoon of soybean flour, 1 teaspoon of finely ground dried small fish, 1 teaspoon of vegetable oil and about 1 cup of clean water. Mix the flours with a little cold water to a smooth paste, stir into boiling water, and cook for at least 10 minutes, stirring. Add the fish powder and oil at the end. Serve it warm and thick enough to stay on a spoon, in a clean cup, within 2 hours of cooking.
Worked example
Worked example 1: reading the trend. Stunting in Rwanda fell from 33% of children under five in 2019–20 to 27% in 2025. Describe the change correctly.
Worked example
Worked example 2: which condition? At a health centre, two children are seen. Child A, 8 months old, is very thin, with loose skin on the thighs, visible ribs and a wrinkled face, and is hungry. Child B, 2 years old, stopped breastfeeding at 14 months, eats mostly cassava porridge, and has swollen feet, thin pale hair and peeling skin. Identify each condition.
Warning
Common mistake. A child with kwashiorkor may look "plump" because of the swelling, so the family may think the child is well fed. Press a thumb gently on the top of the foot for three seconds: if a dent remains, there is oedema, and the child needs a health worker at once.
Tip
Memory hook: "Kwashiorkor is swollen, marasmus is wasted." K for "kwashiorkor" and for "keeps water"; M for "marasmus" and for "muscle and fat gone".
Practice
Sources and credits
