Balanced Meal Preparation
Senior 2 · Home Science
Balanced Meal Preparation
Lesson 1 of 4
20 min
Let's begin
A plate of beans and sweet potato fills the stomach, but does it give the body everything it needs? A meal can be large and still leave a child short of the iron, vitamins or protein needed to grow. Stunting (being too short for one's age because of long-term poor nutrition) is still a serious problem in Rwanda, and it is largely prevented by what goes on the plate, not by how much.
In this lesson you will learn the nutrients the body needs, what each one does, and how Rwandan foods are sorted into food groups. This is the knowledge you need before you can plan a balanced meal.
A nutrient is a substance in food that the body uses for energy, growth, repair or protection. Nutrition is the process of taking in and using food. There are six groups of nutrients, plus fibre:
| Nutrient | Main job | Rwandan sources | Result of too little |
|---|---|---|---|
| Carbohydrates (starches and sugars) | Energy | Sweet potato, cassava, matoke (cooking banana), maize, sorghum, rice, Irish potato | Tiredness, weight loss; with too little protein as well, marasmus |
| Proteins | Growth and repair of body tissues | Beans, peas, groundnuts, soya, milk, eggs, fish (sambaza and tilapia), meat | Poor growth; kwashiorkor (swollen belly and legs) in young children |
| Fats and oils | Concentrated energy; carry vitamins A, D, E, K | Cooking oil, avocado, groundnuts, milk, palm oil | Dry skin, too little energy |
| Vitamins | Protection and regulation of body processes | Vitamin A: orange-fleshed sweet potato, carrots, mango, dark green leaves. Vitamin C: oranges, passion fruit, tomatoes, amaranth | Vitamin A: night blindness. Vitamin C: scurvy (bleeding gums) |
| Minerals | Bones, teeth, blood, body regulation | Iron: beans, amaranth, cassava leaves, meat. Calcium: milk, small whole fish. Iodine: iodised salt | Iron: anaemia. Calcium: weak bones (rickets). Iodine: goitre |
| Water | Transports nutrients, controls body temperature, removes waste | Safe drinking water, milk, soups, fruit | Dehydration |
| Fibre (roughage) | Keeps the gut working, prevents constipation | Beans, whole maize flour, vegetables, fruit with skin | Constipation |
For meal planning, Rwandan schools and health workers usually sort foods by their main job:
Many foods belong to more than one group. Beans give protein, but also carbohydrate, iron and fibre. Milk gives protein, fat and calcium. Classify a food by its main nutrient.
Question: 1 g of carbohydrate gives about 17 kJ of energy and 1 g of fat about 37 kJ. How much energy is in (a) 20 g of carbohydrate and (b) 20 g of cooking oil? How many times more energy does the oil give?
Solution: (a) 20 × 17 = 340 kJ. (b) 20 × 37 = 740 kJ. 740 ÷ 340 ≈ 2.2 times as much. This is why a little oil adds a lot of energy to a meal, and why too much oil leads to weight gain.
Tip
Memory hook: "Go, Grow, Glow". Energy foods help you go, body-building foods help you grow, protective foods help you glow with health.
Exam technique: when asked for a deficiency disease, pair the nutrient and the disease exactly: iron and anaemia, vitamin A and night blindness, iodine and goitre, protein and kwashiorkor.
Sort these foods into the three food groups: matoke, sambaza, amaranth, milk, cassava, passion fruit.
Solution: Energy-giving: matoke, cassava. Body-building: sambaza, milk. Protective: amaranth, passion fruit.
Name the mineral lacking in a person with anaemia, and give two Rwandan foods rich in it.
Solution: Iron. Beans, amaranth, cassava leaves (isombe) or red meat.
Why is orange-fleshed sweet potato better for young children than white-fleshed sweet potato?
Solution: Both give energy, but the orange flesh is rich in vitamin A (from beta-carotene), which protects the eyes and helps fight infection.
How much energy is in 15 g of fat?
Solution: 15 × 37 = 555 kJ.
Summary
Sources and credits
Written by Ganzaa.
