× SuperSmart Learn by health topic New articles Popular articles
Visit our shop My account Smart Prescription Blog Loyalty scheme Language: English
Slimming Guides and tutorials

How many calories should you eat and burn each day?

How can you slim down and lose fat without also losing muscle (and maybe even gain muscle)? We give you the lowdown on daily calorie intake and expenditure.
Woman counting calories
Discover how to manage your ‘calories in vs calories out’ to achieve or maintain your ideal body shape.
Rédaction Supersmart.
2022-03-30Comments (0)

Calories: a measure of energy consumed and expended

Originally, a calorie was the term used for a a unit of energy in physics, 1 calorie corresponding to the amount of energy needed to raise the temperature of 1 gram of water from 14.5°C to 15.5°C at a pressure of 1 standard atmosphere.

Now replaced in physics by the word joule, the term calorie is still used in the field of dietetics to measure the amount of energy provided to the body by food, and the amount of energy expended by the body (1).

In fact, in dietetics and nutrition, the term actually used is kilocalories, not calories. For example:

Basal metabolic rate: the starting point

Basal metabolic rate measures the amount of energy expended by the body at rest: to keep your organs functioning (digestive system, brain, heart, lungs, muscles, etc.), your body has to expend energy (2).

So even if you sit at a desk all day, you will be using energy. However, the amount of energy expended by your body will depend primarily on your body composition, namely your percentage of fat mass and muscle mass: the higher your muscle mass, the more calories you expend at rest.

According to the World Health Organization (WHO): (3-4)

Basal metabolic rate for men

For men, the formula used for calculating basal metabolic rate is: (10.0 x weight in kilograms) + (6.25 x height in centimetres) – (5.00 x age in years) + 5. For example, for a man of 50 who is 1 metre 78 tall and weighs 65 kilos, the basal metabolic rate would be 10 x 65 + 6.25 x 178 – 5 x 50 + 5, which is around 1500 kCal (5).

Basal metabolic rate for women

For women, the formula is: (10.0 x weight in kilograms) + (6.25 x height in centimetres) – (5.00 x age in years) – 161. So for a woman of 50, who is 1 metre 62 tall and weighs 50 kilos, the basal metabolic rate would be 10 x 50 + 6.25 x 162 – 5 x 50 – 161, which is around 1100 kCal (6).

Exercise-related modifiers

Once you have calculated your basal metabolic rate, you then need to apply a coefficient which depends on your level of physical activity:

How many calories do you need to burn to lose weight?

On paper, losing weight is simple: all you need to do is expend more energy than you consume. Your body will then draw on its reserves to make up the difference, and hey presto, you lose weight.

However, if you don’t do any exercise, you will still lose fat mass but your body will also tap into your unused muscle mass, in order to maintain a calorie reserve in adipose tissue.

So the best way of losing weight is to ramp up your level of physical activity, without also increasing your calorie intake: that way, you automatically expend more than you take in. You lose weight while preventing loss of muscle.

Alongside your weight loss diet and exercise programme, it can also help to take dietary supplements that help reduce the storing of fat, to counteract the body’s natural tendency to do just that (such as Garcinia cambogia). (7)

In fact, in order to achieve lasting weight loss without the ‘yo-yo’ effect, it’s best to restrict yourself to a calorie deficit of 10%-20%. In practical terms, this means that if your daily calorie requirement, including physical activity, is 2000 kCal, you need to eat between 1600 kCal and 1800 kCal a day to lose weight (8).

Not all calories are the same!

Nutritional quality comes first!

Be careful, though: not all calories are the same. A food’s nutritional quality is ultimately much more important than its calorie content.

For example, 10 grams of milk chocolate provides the same amount of calories as 300 grams of courgettes, but the chocolate contains a lot of unhealthy carbs and fats.

By way of example, a correctly-proportioned calorie intake is considered to be as follows: (9)

Satiety: friend or enemy of the dieter?

The main difficulty with dieting is managing the hunger that comes from instigating a deficit in calories. That’s why it’s best to choose foods that promote a feeling of satiety without providing lots of calories (10).

We’ve just mentioned courgettes, but there are many other foods that fit the bill. For example, when a craving strikes, eating an apple and drinking a large glass of water will fill you up and kill the urge to snack, at least for an hour or two.

Splitting meals can therefore be a good option: rather than eating 3 large meals a day, have a light breakfast, then a small snack at 10am, a light lunch, a healthy snack at 4pm, and a light dinner in the evening.

You can also take advantage of dietary supplements that promote the feeling of satiety:

In recent years, some superfoods have also become popular with those keen to lose weight, such as dragon fruit (or pitaya), rich in anthocyanins, antioxidants recognised for reducing carbohydrate absorption and increasing cell sensitivity to insulin (13).

In synergy with enzymes involved in the secretion of the satiety hormone, pitaya is therefore well worth considering (try the supplement TropiSlim).

Losing fat, gaining muscle: how to manage calories

In theory, it is not possible to gain muscle and shed fat at the same time. In order to create muscle, the body needs a surplus of calories, while to lose fat, it needs a deficit. On the face of it, the two seem pretty irreconcilable.

Body re-composition

However, if you have a high percentage of fat mass (above 15%), you can, to a certain extent, achieve body re-composition by slightly reducing your calorie intake and taking moderate exercise (especially resistance training, and bodybuilding, at least three times a week) (14).

To do this, however, it’s essential to increase your intake of protein, the main component of muscle. Between 1g and 2g of protein per kilo of bodyweight a day is generally thought to be the amount necessary. For a man weighing 70kg, for example, this represents 70g-140g of protein a day (15).

To reach these levels, it’s therefore important to eat a lot of high-protein foods, in particular, lean white meat (such as turkey) or egg whites. In the case of our example, this would mean eating an average of 300g-500g of turkey a day!

That’s why most bodybuilders choose to take protein in the form of whey powder. Whey is a by-product of cheese manufacture, and a supplement provides a high protein intake in the form of a drink (16).

Losing fat without losing muscle

During a cutting phase, when you’re shedding fat but not muscle, it’s important to maintain a high level of muscle-building. This means keeping up your weight-training workload, while significantly reducing your calorie intake (by 20%).

Since cutting your calories results in fatigue, it can be difficult to constantly maintain this level of physical exertion. That’s why, during these cutting phases in particular, many bodybuilders choose to take BCAAs and creatine. BCAAs are the basic building blocks of muscles, levels of which tend to decline with age, while creatine enables the body to accelerate production of ATP, the energy our muscles need to function (17-18).


  1. HARGROVE, James L. History of the calorie in nutrition. The Journal of nutrition, 2006, vol. 136, no 12, p. 2957-2961.
  2. HARRIS, J. Arthur et BENEDICT, Francis G. A biometric study of human basal metabolism. Proceedings of the National Academy of Sciences of the United States of America, 1918, vol. 4, no 12, p. 370.
  3. https://www.who.int/fr/news-room/fact-sheets/detail/healthy-diet
  4. http://apps.who.int/iris/bitstream/handle/10665/41280/WHO_MONO_61_fre.pdf?sequence=1
  5. BOOTHBY, Walter M. et SANDIFORD, Irene. Basal metabolism. Physiological Reviews, 1924, vol. 4, no 1, p. 69-162.
  6. FASSINA, Patricia, ADAMI, Fernanda Scherer, ZANI, Valdeni Terezinha, et al.The effect of Garcinia cambogia as coadjuvant in the weight loss process. Nutricion hospitalaria, 2015, vol. 32, no 6, p. 2400-2408.
  7. HALL, Kevin D. What is the required energy deficit per unit weight loss?. International journal of obesity, 2008, vol. 32, no 3, p. 573-576.
  8. https://www.vidal.fr/sante/nutrition/equilibre-alimentaire-adulte/recommandations-nutritionnelles-adulte.html
  9. DRAPEAU, Vicky, KING, Neil, HETHERINGTON, Marion, et al.Appetite sensations and satiety quotient: predictors of energy intake and weight loss. Appetite, 2007, vol. 48, no 2, p. 159-166.
  10. PAPAKONSTANTINOU, Emilia, ORFANAKOS, Nickolaos, FARAJIAN, Paul, et al.Short-term effects of a low glycemic index carob-containing snack on energy intake, satiety, and glycemic response in normal-weight, healthy adults: results from two randomized trials. Nutrition, 2017, vol. 42, p. 12-19.
  11. GOUT, Bernard, BOURGES, Cédric, et PAINEAU-DUBREUIL, Séverine. Satiereal, a Crocus sativus L extract, reduces snacking and increases satiety in a randomized placebo-controlled study of mildly overweight, healthy women. Nutrition Research, 2010, vol. 30, no 5, p. 305-313.
  12. TENORE, Gian Carlo, NOVELLINO, Ettore, et BASILE, Adriana. Nutraceutical potential and antioxidant benefits of red pitaya (Hylocereus polyrhizus) extracts. Journal of functional foods, 2012, vol. 4, no 1, p. 129-136.
  13. SARDELI, Amanda V., KOMATSU, Tiemy R., MORI, Marcelo A., et al.Resistance training prevents muscle loss induced by caloric restriction in obese elderly individuals: a systematic review and meta-analysis. Nutrients, 2018, vol. 10, no 4, p. 423.
  14. NUNES, Everson A., COLENSO‐SEMPLE, Lauren, MCKELLAR, Sean R., et al.Systematic review and meta‐analysis of protein intake to support muscle mass and function in healthy adults. Journal of Cachexia, Sarcopenia and Muscle, 2022.
  15. DEVRIES, Michaela C. et PHILLIPS, Stuart M. Supplemental protein in support of muscle mass and health: advantage whey. Journal of food science, 2015, vol. 80, no S1, p. A8-A15.
  16. HORMOZNEJAD, Razie, ZARE JAVID, Ahmad, et MANSOORI, Anahita. Effect of BCAA supplementation on central fatigue, energy metabolism substrate and muscle damage to the exercise: a systematic review with meta-analysis. Sport Sciences for Health, 2019, vol. 15, no 2, p. 265-279.
  17. XIONG, Qiang, DU, Fei, ZHU, Xiaohong, et al.ATP production rate via creatine kinase or ATP synthase in vivo: a novel superfast magnetization saturation transfer method. Circulation research, 2011, vol. 108, no 6, p. 653-663.


You must be connected to your account to leave a comment
Be the first to review this article
Our selection of articles
Excess visceral fat
Visceral fat: 7 tips to help you lose it naturally

Visceral fat is a particular type of adipose tissue stored around the abdominal organs. In excess, it poses a risk to health ... Here are 7 tips to help you eliminate unwelcome visceral fat.

Post-childbirth belly
How to lose your post-baby tummy

Flabby, untoned … After the joy of having a baby, many young mums feel dismayed by the state of their tummies. Read on for our tips on how to tone this area of the body after childbirth.

Water retention in the stomach
How to reduce water retention in the stomach

Water retention is a common problem characterised by excessive fluid accumulation in tissues. Here we explore how to reduce water retention in the stomach.

Ketogenic diet with meat, fish, eggs, avocados and the word keto
Why start a ketogenic, or keto, diet?

The keto diet, high in fat, produces rapid weight loss. Here’s a quick rundown of what you need to know before launching into a diet of this kind.

Woman taking exercise to lose weight and slim down
What is lipolysis?

Lipolysis is the body’s mechanism for breaking down fats to make them absorbable and usable. There are two types: gastrointestinal lipolysis, which takes place during digestion, and adipocyte lipolysis, concerned with stored fat, which is often referred to as ‘fat-burning’. How can you use it to help achieve your slimming goals?

Drink green tea to lose weight
Green tea for weight loss: does it really work?

It’s been said that it cleanses and detoxifies the body, burns fat and suppresses the appetite … In short, it’s credited with many benefits, due in particular to its high content of powerful flavonoids called catechins. But can green tea really help you lose weight?

Products which must be of interest

© 1997-2024 Supersmart.com® - All rights reserved
© 1997-2024 Supersmart.com®
All rights reserved
We use cookies (first-party and third party) to give you the best online experience.
Learn more about cookies and manage my preferences
I accept cookiesx