Nutrition Myths


  • “Calorie calculation” is an outdated and unreliable method used by many weight loss programs. It ignores key factors that play a crucial role in how energy is burned and transformed to fatty tissue.
  • The “Calories in, Calories out” formula is also flawed, since it doesn’t take into consideration the inter-dependencies of its components, such as the thermic energy of energy nutrients, body composition and eating patterns.
  • The most significant and adjustable variable that either makes us accumulate or burn more fat is the type of foods we consume.  This is particularly true of the type of energy nutrients that are dominant in our diet.


Should we count Calories to lose or maintain weight?

Calories are a crucial factor in maintaining a balanced weight. But is counting Calories and controlling Calories intake an effective method in weight loss or management programs? Find here why counting Calories should not be used.

What is calorie counting?

Weight loss programs that use calorie counting techniques are based on the First Law of Thermodynamics without understanding the intricacies and complexities of the human body’s physiology.

The First Law of Thermodynamics in simple terms says that the:

“Change in the internal energy of a closed system is equal to the amount of energy entering the system minus the amount of energy leaving the system”.

This law applies to everything in nature and, therefore, applying it to the weight management methodology sounded convincing.

The dietary version of this law says that:

“You will gain weight when the amount of Calories from your diet is higher than Calories you burn”.

This statement, as well as many diets that use this principle, seem to ignore the key factor in weight loss or weight management – the type of food you eat regulates how your body burns fat.

In other words, this principle says that: if you want to lose weight, as long as you keep the Calories from your diet below what you burn as energy, you’ll be fine. However, if you have more Calories from food than the Calories you burn, your body will accumulate fat.

This can be represented by this formula:

Net weight gain/loss = Energy from diet – Energy expended

Why is calorie counting not that important?

Relying on calorie calculations can be misleading and lead to incorrect results, since there are other key factors for weight loss/management that are being completely ignored.

First, this formula needs clarification, since the energy expanded includes the following inter-dependent sub-components:

  1. Digestive processes (breaking down food);
  2. Basal metabolism (energy burned when resting);
  3. Daily activity (what we burn during our day-to-day activities);
  4. Exercise (physical exercise – anything outside our day-to-day activities).

Some of these components are usually not taken into consideration in the calculations.

The formula, therefore, becomes more complex:

Net weight gain/loss = Energy from diet – Energy burned through the digestive process – Energy burned through basal metabolic rate – Energy burned through day-to-day usual activities – Energy burned through physical exercise

The following are the reasons why this formula is flawed, due to the inter-dependency of its components and some crucial factors of our body’s physiology.

  1. We metabolize energy nutrients differently depending on what we eat

    The main flaw of using this formula is not recognizing the importance of the differences in metabolizing energy nutrients.

    A diet high in fat and low in carbohydrates reduces insulin resistance (improves insulin sensitivity). This results in the release of fat deposits from the adipose tissues, using them as an energy source. This is the reason why we lose weight so quickly on a high fat/low carbohydrate diet.

    A great example of this is the ketogenic diet. If you switch to the ketogenic diet, your body quickly adjusts (in about 3 weeks) to burning fat, rather than carbohydrates, as a primary source of fuel.

    A diet high in carbohydrates, on the other hand, uses mostly dietary carbohydrates as a source of energy. This increases the insulin production and is linked to increase in insulin resistance. The adipose tissue slows down the release of fatty acids for energy needs.

    A high carbohydrate diet also increases the production of fatty acids and cholesterol.  Carbohydrates are not as efficient as fats in sending a satiety signal to the brain. This is the reason why it is easier to exceed the desired calorie intake.

    The bottom line is that the same amount of Calories on a high carbohydrate diet will accumulate more fat in the adipose tissue than on a high fat diet, resulting in different energy expenditures.

  2. The thermic effect of nutrients

    The type of food we eat influences how much energy is spent during its digestion, absorption and disposal.

    For instance, depending on the information source, the thermic effect of proteins is 20%-35%, of carbohydrates 5%-15% and of fat has shown mixed results, with some studies showing 0-3% with others an average of 7%. (1, 2, 3, 4)

    What do these percentages mean?

    Here is an example: if the thermic effect of a certain protein is 20%, it means that when you have 100 Calories worth of it, 20 Calories will be used during its digestion, absorption and disposal.

  3. Level of physical activity depends on what we eat

    What we eat, influences the pattern of our energy levels after the meal.

    For instance, eating a sweet snack will boost your energy temporarily, causing an increase of insulin. The excess of insulin will make you tired and sleepy, drastically reducing the energy levels and the energy required for physical activity – meaning less exercise and, therefore, less energy burned.

    A sustained energy intake, however, (such as in high fat or high vegetable diets) will provide you with a steady energy level during a longer period. You will be likely more active and burn more energy.

  4. What we eat for the first meal will influence what we eat for the following meal

    What we eat, influences what we will eat in the following meals.

    For instance, if you eat a muffin for breakfast, it is likely that your next meal will be sooner and that it will be another sugary snack. This happens due to the excessive insulin release after the first muffin and the sudden drop of the blood sugar levels. This leads to fatigue and craving for more carbohydrates of the same type.

  5. Our body composition influences the thermic energy of foods

    Imagine two men, each weighing 200 pounds (90.7 hg). One is an athlete/body builder and has a high muscle to body fat ratio. The other man is obese. An obese person expands much less energy from foods during and after exercise and during rest, than a lean person of the same body weight. (5)

    These are just some of the reasons why relying on the formula for counting Calories, that has inter-dependent variables, simply doesn’t work for controlling weight or sustaining good health.

Mathematical examples

To make it clear how inter-dependent components work, I would like to demonstrate by a simple mathematical example. This will show you why the concept of calorie counting is not reliable.

In this case variables B and C are dependent of each other (meaning that if B changes C changes as well):

If you want A to become 9 you would expect that it is sufficient to reduce B or C by 1. However, because C is dependent on B, it may increase to 7. The result could actually look like this:
No change=B is reduced by 1+C got incremented

The same happens with the calorie calculation formula, due to the dependencies described above.

Here is a specific example using any online calorie calculator. I used this particular one.

Please note that the numbers used in this example are there to illustrate how complex and unreliable this formula is.

Nutritionists and dieters have an idea of how each component behaves, but it would be extremely difficult and completely impractical for them to calculate with precision some components of this equation, due to numerous influencing factors. (6)

For example, the basal metabolic rate is influenced by many variables and can change significantly depending on the foods you consume. Some foods, for instance, can alter the basal metabolic rate by 50% (such as whole foods vs. processed foods). (7)

In this simplified example, we have a 160cm tall woman (let’s call her Julia), 40 years of age  who weighs 60kg. She wants to lose 1kg per week and uses an online calorie calculator to see how much she needs to reduce her calorie intake. Let’s assume a realistic situation that Julia’s diet mainly consists of processed foods and is high in carbohydrates. She is relying on how much Calories go in and out of her system to achieve her goal.

Net body weight gain/loss=Calories from the current diet- Calories expanded through basal metabolic rate- Calories expanded through daily activity- Calories expanded through exercise
Current body weight and energy balance
Julia wants to reduce her weight by 1kg in 1 week. Calculation from Calorie calculator suggests that she should be on 920 Calories daily to reach 59kg at the end of the week ideally keeping her usual physical activities the same. This is what she think she can achieve:
What she doesn’t know is that by eating processed foods, carbohydrates or through fasting, her metabolism slows down. Fasting can reduce the basal metabolic rate by up to 15% and eating processed foods by about 50%. High amounts of carbohydrates can increase insulin resistance and instead of releasing fat from the cells for energy needs, it stores it. This means that instead of reduction in body fat she may end up increasing her fatty tissues, and reducing her lean body mass. Lack of energy from food would not allow her to exercise and her day to day activities would also be reduced. If her metabolism goes down by 50% after one week, and she stops exercising due to lack of energy, so she might actually gain a little weight:
If Julia doesn’t change what she eats, counting calories will be irrelevant.

NOTE: These calculations in real life are actually much more complex. However, it will hopefully give you an idea of how difficult and inaccurate counting Calories can be.


You will find a summary of the most common nutrition myths and evidence-based nutrition facts here.

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