The Basics of Nutrition © British Nutrition Foundation 2004

Why do we eat food? We eat food because our bodies need: energy; compounds for growth, repair and reproduction; substances to regulate the production of energy, growth and repair. © British Nutrition Foundation 2004

What do our diets contain? A balanced diet contains a wide variety of foods Food contains a mixture of different nutrients which have different functions in the body. A healthy diet will provide adequate amounts of all nutrients needed by the body for good health. © British Nutrition Foundation 2004

The energy supply Foods containing… protein carbohydrate fat …provide the body with energy. © British Nutrition Foundation 2004

The other functions Food also provides… fibre; water; vitamins and minerals. These substances do not provide the body with energy, but are all needed to fulfil some important ‘support’ functions for the body. © British Nutrition Foundation 2004

How is energy measured? Energy is measured in units known as kilojoules (kJ). Energy is also measured in calories (kcal). This is a different way of measuring energy, just as distance is measured in centimetres and inches. 1 calorie = 4.2 kJ © British Nutrition Foundation 2004

Energy and nutrients Food and drinks provide us with different amounts of energy because of the variety of nutrients they contain. 1g protein provides 17kJ (4 kcal). 1g carbohydrate provides 16kJ (3.75 kcal). 1g fat provides 37kJ (9 kcal). © British Nutrition Foundation 2004

© British Nutrition Foundation 2004

How is the energy released from food? In order to release the energy contained in food, it needs to be broken down. The breakdown of food to release energy is called ‘digestion’. Digestion is the breakdown of food molecules into small units that can be absorbed. Digestion starts in the mouth with chewing, it then continues to the stomach, small intestines and large intestines. © British Nutrition Foundation 2004

Energy balance Different people need different amounts of energy. It is important to balance the amount of energy we eat with the amount of energy we use up. Keeping our bodies active helps to keep us healthy. Some activities use more energy than others. © British Nutrition Foundation 2004

Energy balance Too much energy from food and drink is stored as fat in the body. Eat the right amount to be a healthy weight. As we get older the amount of food we need changes. © British Nutrition Foundation 2004

Energy in vs Energy out These foods provide 400kJ of energy: © British Nutrition Foundation 2004

Energy in vs Energy out Number of minutes to use up 400kJ of energy: © British Nutrition Foundation 2004

Enjoy your food and keep active! © British Nutrition Foundation 2004