Calories and weight loss
Calorie counting is a way of keeping track of the energy in the food and drinks you have. It helps you see what you're eating and drinking so you can make healthier choices.
This page explains what calories are and how calorie counting can work to help you reach a healthy weight.
What are calories?
Calories are units of energy in an item of food or drink.
Your body uses this energy all day long for:
- basic functions like breathing and keeping your heart beating
- movement and exercise
- digesting the food you eat
You will see the number of calories in an item listed on the packaging as "kcal".
Why calories matter for weight loss
If we regularly eat and drink more calories than the body needs, the extra energy is stored as fat over time.
To lose weight, we need to use more energy than we take in, which creates a calorie deficit. When we're in a calorie deficit, our body relies on its fat stores for fuel.
How many calories should I have to lose weight?
Most adults in the UK eat and drink more than their body needs. When we consistently take in more energy than we use, we gain weight.
To stay at a healthy weight, the recommended average daily amount is:
- 2,000 calories a day for women
- 2,500 calories a day for men
If you are currently overweight, you might be eating and drinking more calories than you need.
If you are not sure whether your weight is in a healthy range, you can check using the NHS BMI calculator.
Reducing calories to lose weight
To lose weight, you need to eat and drink fewer calories than you do now. Aim to reduce your intake by around 600 calories a day. This is a safe and sustainable way to lose weight.
Did you know?
Regular exercise can help you manage your weight and boost your mood. Start with 15 minutes a day and build up gradually.
How to count calories
If you are going to start counting calories, the first thing to do is look at how many calories are in the food and drinks you have on a typical day. This can give you a clear picture of your usual habits.
Once you have your total for the day, you can see exactly where to cut around 600 calories. Here are a few ways you can count your daily calories:
Use the NHS Weight Loss Plan app
The NHS Weight Loss Plan app lets you set a weight loss goal, select your portion sizes, and keep track of your calories throughout the day.
Check the labels on shop-bought foods
If you want to count calories without an app, you can find the information on the food packet. This helps you compare different food and drink products at a glance.
Calories are usually listed as kcal and shown per 100g or 100ml, or per portion.
Be aware that the manufacturer's portion size might be different from yours.
Try weighing your portions
When you are starting out, it can be really helpful to weigh your portions. You should do this before cooking your food.
This is because the portion on the label might be smaller than the amount you actually eat.
For example:
- A packet of rice says that a 75g portion is 260 calories.
- If you cook a larger amount and your portion is 150g, you are having 520 calories.
This isn't something you have to do forever. It just helps you see if your usual serving matches the portion size on the packet.
Keep a food diary
Having a daily record of everything you eat and drink can make it a lot easier to keep track of your calorie intake.
Remember to include the calories in:
- alcohol, fizzy drinks, and juices
- the oil and spreads you have cooked with
- any toppings or accompaniments, like cheese or yoghurt
- sauces, such as mayo and ketchup
How to reduce your daily calories
Once you know how many calories are in your usual meals, you can look for ways to have 600 calories less across the day. You do not have to change everything at once. It can help to divide that 600 calorie reduction into smaller steps throughout the day.
Example of how to reduce your daily calories
Breakfast
Cut around 100 calories from your breakfast.
Try to weigh cereal and stay away from jam and chocolate spreads.
Lunch
Cut around 200 calories from your lunch.
Check labels on shop-bought food and go for water or sugar-free drinks.
Dinner
Cut around 200 calories from your dinner.
Try to limit ready meals and takeaways and cook healthy meals from scratch instead.
Snacks
Cut around 100 calories from your snacks.
Swap crisps and chocolate for fruit or plain popcorn.
Check out our recipes on the Healthier Families website for step-by-step recipes that are all under 600 calories per portion.
What do I do when I reach my healthy weight?
Once you reach a weight that is healthy for you, you can stop recording every meal.
Your goal is now to learn which habits help you stay at that weight. Here are some simple ways to stay healthy without counting calories.
Monitor your progress
Notice how your body feels. For example, you might feel that your clothes are looser or that walking feels easier.
Stay active
To help keep the weight off try to stay active for 60 to 90 minutes a day. This does not need to be intense exercise. It can be things like:
- taking the stairs instead of the lift
- doing some gardening or housework
- going for a walk or swim
Eat well
Eat a healthy, balanced diet with a variety of foods from the different food groups. Read our guide on healthy eating to learn about healthy choices and portion control.
The best routine is one that works for you and that you can keep doing.
Get a free 12-week weight loss plan!
The NHS Weight Loss Plan app is more than a calorie tracker.
It gives you a free 12 week plan to help you adopt healthier habits to lose weight, for good!
With the app, you can:
- set your weight loss goal
- track what you're eating
- set a daily calorie target
More than 4 million people have already downloaded the NHS Weight Loss Plan app to help them lose weight. Join them today.
Dietary advice
We cannot give health advice to every person individually.
Before you make changes to your lifestyle to lose weight, talk to a GP or a healthcare professional if you have:
- a medical condition
- a special diet for your health
- an eating disorder (or have had one in the past)
If you need more information or support with eating disorders, the charity Beat Eating Disorders has lots of help for adults and children.
Healthy eating to lose weight
Counting calories is not the only way to lose weight. Things like changing portion sizes and making sure your meals are balanced can also help. Learn more from our guide on healthy eating.