Energy contained in food and drink is measured in units called kilocalories, or more commonly calories. On food labels you will see this written as kcal.
The recommended daily amount (RDA) of energy intake for adults is about 2,000 calories for women and 2,500 for men. We need less as we get older.
Two-thirds of the energy we should take in is used to control our body temperature and for other activities, such as digesting food or making new tissues. The rest of the energy we use up during physical activity. When we take in more energy than we use up, this is stored as fat and we gain weight.
To lose weight you need to burn off more energy than you take in. You can do this by:
- reducing the amount of calories you take in through food and drink
- increasing the amount of energy you burn off through physical activity.
Many weight loss programmes are based on calorie-controlled diets. This section looks at eating different food types in healthy amounts to help reduce the amount of energy you take in. This can help you lose weight, especially if you also increase your physical activity.