Weight loss is about consuming fewer calories than you burn for energy, so cutting your calorie intake can cause weight loss.
As we get our calories from the food that we eat, it makes sense to reduce our food intake to lose weight but exercise can also help as it burns off some of the calories you’ve eaten.
A general rule of thumb for reducing calories for weight loss is to reduce your calorie intake to 500 fewer than the amount you burn every day.
For example, if your body burns 2000 calories a day, reducing your intake to 1500 calories a day should result in a loss of around 1lb a week.
This might seem like a slow weight loss, but it’s actually what’s recommended by the NHS, as losing 1-2lbs a week is healthy and sustainable in the long term.
Diet culture can often make it seem like we’re expected to lose large amounts of weight in a fairly short time but this isn’t just unrealistic, it can be dangerous too.
Our specialists recommend a slow and steady weight loss, which you can achieve by reducing your calories by 500 a day.
This may seem like a lot, but it isn’t considered a drastic change and you should still have more than enough calories for a healthy, balanced diet with a couple of treats along the way.
How many calories do I need to keep a healthy, sustainable diet?
The NHS state that men need around 2,500kcal daily and women need around 2,000kcal a day.
These guidelines indicate the number of calories needed to maintain a healthy body and BMI.
Eating more calories than this (a calorie surplus diet) over a prolonged amount of time could cause weight gain, but eating less than this amount (calorie deficit diet) over a few weeks or months could cause weight loss.
Does exercise affect my calorie intake?
The amount of exercise that you do can also affect your calorie allowance or how much you should reduce by.
For example, if you’re fairly physically active, you won’t need to reduce your calories as much as someone with a sedentary lifestyle to lose weight.
This is because you will also be burning calories for energy whilst you’re active — if you burn 200 calories exercising then you may only need to reduce your food intake by 300 instead of the full 500.
Will cutting calories slow down my metabolism?
Cutting your calorie intake by a sensible amount shouldn’t slow down your metabolism, but if you drastically cut calories you could be in for a surprise.
If you consistently eat much less than your body needs, your metabolism can slow down which can stall weight loss.
It’s important to make sure you’re eating enough food to nourish your body.
Ideally, you’ll need to eat anywhere between 1,500-2,000kcal daily to lose weight and should not let your intake dip below 1200 calories a day often.
How do I know how many calories I’m consuming?
A great way to keep track of your calorie intake is to start a food diary.
You can use an app or a pen and paper diary or notebook to track everything you eat each day and how many calories you’re taking in as a result.
It’s often a good idea to start your food diary before you begin to cut calories, as this will give you a better idea of how much you’re eating every day — warning, you may be surprised when it all adds up!
With that being said, the actual number of calories you’re eating every day isn’t as important as making healthy changes.
Whether you need to reduce or increase your calories to help your body, knowing where you’re currently at is important for monitoring progress.
Now you know where your starting point is, you could try making small and gradual changes to cut calories, such as:
- Swapping to some lower-calorie food options
- Reducing your alcohol intake if you drink
- Changing your cooking methods to use less fat or oil
- Slowly reducing your portion sizes
What if I cut too many calories?
It’s always best to cut your calories gradually and in a manageable way.
If you cut your calorie intake too much too quickly, you could find it difficult to keep up with the change, leading you to give up on your weight loss journey altogether.
That isn’t the only reason to reduce your calorie count gradually though, you may be surprised to learn that a drastic reduction could cause more harm than good.
If you reduce your calories by too much at once, you may experience some nasty side effects, including:
- Gallstones (due to rapid weight loss)
- Decreased metabolism
- Malnutrition
- Difficulty sleeping
- Mood changes/swings
- Constipation
We understand that it may be tempting to reduce your calories quickly, but trust us, slow and steady will make sure that your weight loss is safe and sustainable.
Your health is the most important thing here, after all.
If you aren’t sure how many calories you should be eating for weight loss, please speak to your GP or healthcare team.
You can ask for a referral to a dietitian or nutritionist who should be able to give you more personalised advice for your needs.
They may also refer you to the NHS’s weight management service, which includes advice about healthy eating, calorie intake, and medical options that could help make your diet easier.
Want to learn more about weight loss?
Here are some more of our articles that will help you along your weight loss journey.
