Understanding calories

The amount of energy in food or drink is measured in calories.

Why calories are important

You need energy from calories for your body to work properly. Your body uses this energy to function properly.

To stay at around the same weight, the calories your body uses should be the same as the amount of calories you eat and drink.

If you do not use the same amount of calories as you eat and drink, your body weight may change. For example:

Daily calories

Calorie information is often given in kcals, which is short for kilocalories. It may also be given in kJ, which is short for kilojoules.

As a guide:

This could be different based on your:

BMI calculator

Body mass index (BMI) is a measurement that works out if you're a healthy weight for your height.

Find out your BMI

Tips for calorie awareness


Further information

The Eatwell Guide

Find out how to have a healthy, balanced diet.

The Eatwell Guide

Calorie counting

Find out more about counting calories and how it can help you lose weight.

Calorie counting on NHS Better Health

Healthier food swaps

Cut down on sugar, salt and fat in your family's diet with these healthier swaps.

Visit the NHS Healthier Families website

Understanding food labels

Food labels can help you make healthier food choices. Find out about the colour coding system and what to look out for.

Food labels