How low should a low calorie diet go?
Eat about 600 calories a day less than now. If you eat the average 2,000 a day, that’s 1,400, or 1,900 if you eat 2,500. At 1,200 or less, NICE wants a specialist team involved.
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What is a low calorie diet?
For most people, it just means eating less than you do now. The NHS says to cut around 600 calories a day. It calls that a safe and sustainable way to lose weight.
On average, a woman needs 2,000 a day and a man 2,500. Take 600 off and you get 1,400 and 1,900. Your own need could differ with your age, weight, height and how much exercise you do.
Doctors use the name for something stricter. NICE calls 800 to 1,200 a day a low calorie diet.
It’s only for people living with obesity, or overweight with type 2 diabetes. Even then, NICE says to consider it only with long-term support from a specialist weight or diabetes service, for 12 weeks at most.
- Below 800 calories a dayNICE: very low calorie. Specialist service only.
- 800 up to 1200 calories a dayNICE: low calorie. Specialist support, 12 weeks at most.
- Above 1200 calories a dayNHS: eat about 600 less than you do now.
Sources: NICE NG246; NHS
That’s why a 1,200 plan should come with a team. The NHS says very low calorie diets are not suitable or safe for everyone.
Your first step: add up what you eat and drink on a typical day. Then take about 600 off that total.
Should I eat 1,200 or 1,500 calories a day?
It depends on where you start. A 1,500 day is the NHS cut only if you usually eat about 2,100.
| You usually eat | Plan for about | What to know |
|---|---|---|
| 1,800 a day | 1,200 a day | NICE low calorie band. Ask a GP or dietitian first. |
| 2,000 a day | 1,400 a day | The NHS average for a woman. |
| 2,100 a day | 1,500 a day | The high protein day further down. |
| 2,500 a day | 1,900 a day | The NHS average for a man. |
Sources: NHS; NICE NG246
So two people on 1,500 can be making very different cuts. If 600 off takes you to 1,200 or below, talk to a GP or dietitian before you start. Our guide on whether 1,200 calories is safe explains why.
The NHS suggests aiming to lose 0.5 to 1kg a week, and weighing yourself regularly to check. For help finding your number, see how many calories to eat to lose weight.
What does a 350 or 500 calorie meal look like?
Normal food, in a set portion. Every recipe on the NHS Healthier Families site is under 600 calories a portion.
| Meal | Calories | Protein |
|---|---|---|
| Haddock florentine | 322 | 37g |
| Prawn jambalaya | 342 | 17.9g |
| Turkey tikka kebabs | 376 | 37.5g |
| Salmon and broccoli pasta | 465 | 34.2g |
| Macaroni cheese with tomatoes | 517 | 21.4g |
Sources: NHS haddock florentine; NHS prawn jambalaya; NHS turkey tikka kebabs; NHS salmon and broccoli pasta; NHS macaroni cheese
Each number is one serving, a quarter of the recipe. Cooking for one? Split the rest into equal boxes so the next portion is the same size.
Looking for very low calorie meals? A bowl of the NHS easy vegetable soup is 100 calories. That makes a light lunch or a starter, not a day’s food.
A whole day under 800 is a very low calorie diet. NICE keeps it for people with obesity and a clinically assessed need to lose weight fast, such as before surgery.
Soup and shake plans also have a place. One NHS programme for type 2 diabetes with obesity or overweight uses 800 to 900 calories a day for 12 weeks, with support. If you have type 2 diabetes and want to know more, ask your GP if it’s right for you.
What does a 1,500 calorie high protein meal plan look like?
| Meal | Try | Calories and protein |
|---|---|---|
| Breakfast | Scrambled eggs on mushrooms with grilled peppers | 369, 21.3g |
| Lunch | Caribbean chicken salad | 349, 25.5g |
| Dinner | Chilli con carne | 488, 30g |
| Snack | Greek yoghurt and raspberry chill | 129, 6.6g |
| Snack | Breakfast fruit salad | 117, 6g |
Sources: NHS scrambled eggs; NHS chicken salad; NHS chilli; NHS yoghurt chill; NHS fruit salad
That adds up to 1,452, leaving a little room for milk in tea or coffee. Swap any meal for one from the table above with a similar count.
Swap the chilli for turkey tikka kebabs and drop the yoghurt chill, and the day is about 1,210 calories and 90g of protein. Only plan this low if it’s about 600 less than you eat now, and see the GP section first.
How much protein is high? The adult reference is 0.75g per kg of body weight. That works out at about 56g a day for a 75kg man and 45g for a 60kg woman.
Some weight loss research aims higher. One review suggests 1.2 to 1.6g per kg a day, possibly with at least 25 to 30g at a meal, may help appetite and weight.
The NHS says protein at each meal can help you feel full for longer. This day gets 25.5g at lunch and 30g at dinner.
For more swaps, see high protein low calorie meals and protein for weight loss.
How do I stick to calorie controlled meals?
Six NHS habits that keep your count honest
- Add up a typical day first, then find where to cut about 600.
- Split the cut: about 100 at breakfast, 200 at lunch, 200 at dinner and 100 from snacks.
- Weigh food before you cook it, while you learn what a portion looks like.
- Check the portion on the label, as the maker’s portion may be smaller than yours.
- Count drinks, cooking oil, spreads, toppings and sauces like mayo and ketchup.
- Fill about half your plate with veg, and swap crisps and chocolate for fruit or plain popcorn.
Rice shows why weighing helps. In the NHS example, a 75g portion is 260 calories, but a 150g portion is 520.
Healthy food still counts. The NHS says you can gain weight if you regularly eat more than your body needs, even from healthy foods.
The free NHS Weight Loss Plan app lets you set a goal, pick portion sizes and track your calories. Hungry between meals? Try these low calorie filling foods.
When to speak to a GP
Talk to a GP before you change how you eat if you have a medical condition or a special diet for your health. The same goes if you have an eating disorder, or have had one. Also book an appointment if:
- Your plan would take you to 1,200 a day or less. NICE keeps this for specialist weight services.
- You take medicines and plan a low calorie diet. NICE says to review them first.
- Your BMI is overweight or obese and you want help to lose weight, your waist is more than half your height, or obesity runs in your family.
- Your BMI is overweight or obese and you have pre-diabetes, diabetes, high blood pressure, joint pain, high cholesterol, sleep apnoea or heart and blood vessel disease.
- You have, or think you may have, an eating disorder, such as binge eating. Signs include eating very little, exercising too much or very strict food routines, so see a GP as soon as you can.
Never stop or change a prescribed medicine without your prescriber.