Unit 5. Important Materials in Your Food

Learning Objectives

By the end of this lesson, students will be able to:
- Identify the five essential components in food
- Explain the role of proteins, carbohydrates and fats
- Name important sources of proteins, fats, vitamins and minerals
- Use Modal verbs correctly

Theory

Foods contain different materials that help your body to stay strong and healthy. The most important of these are known to be proteins. They are absolutely necessary for building and repairing our bodies. Proteins consist of carbon, hydrogen, oxygen, nitrogen and other elements such as phosphorus and sulfur. The richest sources of proteins are animal foods (meat, fish, cheese, eggs, milk) and some vegetable foods (soya beans, bread, peas).

Sugars and starches, known as carbohydrates, are digested rather quickly and supply energy for the body. Foods rich in carbohydrates are fruit, honey, bread, cakes, potatoes, rice and macaroni.

Fats are also made up of carbon, hydrogen and oxygen. Fatty foods are good sources of energy, but people who eat too much of them become overweight. Fats are found in butter, cream, milk, oily fish, meat, olive oil and sunflower seed oil.

Your body also needs vitamins and minerals. They are present in small amounts but are extremely important for the proper functioning and growth of the body.

Three of the most important minerals are calcium, phosphorus and iron. Calcium and phosphorus work together to make bones and teeth strong. Iron is needed for hemoglobin in the blood. Iodine is necessary for the thyroid gland.

Key Terms

proteins, carbohydrates, fats, vitamins, minerals, amino-acids, hemoglobin, calcium, phosphorus, iron, iodine, energy, building and repairing

Exercise

1. Answer the questions:
1. What are the main elements that make up proteins?
2. Name three sources of fats mentioned in the text.
3. Why are vitamins and minerals important?
4. What role do calcium and phosphorus play together?
5. What kind of food is rich in iodine?

2. Match the nutrients with their main function:
1. Proteins a. Supply energy quickly
2. Carbohydrates b. Building and repairing the body
3. Fats c. Provide energy and insulation
4. Calcium d. Form bones and teeth
5. Iron e. Carry oxygen in the blood

Mini Quiz

1. Proteins are necessary for ________ the body.
a) only energy
b) building and repairing
c) only taste

2. The red colour of the blood is the colour of ________.
a) calcium
b) hemoglobin
c) phosphorus

3. Sea foods are rich in ________.
a) iron
b) iodine
c) calcium