Calories are a measure of the amount of energy in food. Knowing how many calories are in our food can help us to balance the energy we put into our bodies with the energy we use. That’s the key to a healthy weight.
We measure the amount of energy contained in an item of food in calories, just as we measure the weight of that item of food in kilograms.
If you’re trying to lose weight, it’s a good idea to eat less and be more active. Eating less is important when you're trying to lose weight, even if you already have a balanced diet.
You can check whether you’re a healthy weight by using our BMI healthy weight calculator.