Nutrition and the Balanced Diet — Calorific Values, BMI and the Deficiency Map

Nutrition Is a Numbers Chapter

Most students revise nutrition as a list of vitamins and the diseases they prevent — then lose the mark, because the question asked them to *calculate* something.

Nutrition in a competitive paper has two halves:

• ›The table half — which nutrient, which source, which deficiency disease. Pure recall.
• ›The arithmetic half — energy in a meal, BMI, and the make-up of a balanced diet. Pure formula.

The second half is where the free marks sit, because only three numbers do all the work: carbohydrate gives 4 kcal per gram, protein 4 kcal per gram, fat 9 kcal per gram.

Six components make up every diet: carbohydrates, proteins, fats, vitamins, minerals and water. The first three are macronutrients — they supply energy and are needed in large quantity. Vitamins and minerals are micronutrients — needed in milligrams, yet a shortage of any one of them produces a disease with a name.

Roughage, or dietary fibre, supplies no energy at all, and no diet is balanced without it.

1. The calorific value of 1 gram of fat is approximately:

2. A 100 g food packet contains 60 g carbohydrate, 12 g protein and 8 g fat. Its total energy value is:

3. The Body Mass Index (BMI) is expressed in which unit?

4. A person weighs 68 kg and is 1.75 m tall. What is his BMI, and in which band does it fall?

5. In the laboratory, the energy value of a food sample is determined using a:

6. Which of the following is a fat-soluble vitamin?

7. Deficiency of iodine in the diet causes:

8. Swelling (oedema) of the face, legs and abdomen in a young malnourished child is the characteristic sign of: