Why Am I Fat – Misconceptions

In the first part of articles about gaining weight I made an introduction about the entire process, and now I will say a few words about the most common misconceptions when it comes to gaining weight. More specifically, focusing on unimportant matters.

Do carbs and proteins turn into fat?

Many believe that excess of carbs and proteins simply turn into fat which then accumulates right where we don’t want it to. But does that really happen?

The process of turning carbohydrates (glucose) into fats, de novo lipogenesis, takes up energy. The body does not throw the energy around because it evolved during the lack of food (energy). So it utilizes a different, much simpler and more efficient mechanism of accumulating fat tissue.

In short, it involves enhancing the carbohydrate ratio in the process of energy consumption (“fuel burnt”) and storing it as glycogen in order to store fats with no extra energy inversion.

The exception from this are situations in which calorie value of carb intake comes close to total energy consumption – in this case extra parts can only be stored through metabolic reconstruction. These situations happen with very big and permanent calorie sufficits where carbohydrates make the majority of the calorie intake.

Where protein to fat conversion is concerned, the process is even less efficient because it includes amino acid reconstruction from protein to glucose, and then from glucose to fatty acids. I must say that the body doesn’t work on on/off principle, so a certain amount of fat is produced from glucose reconstruction under normal conditions, but these numbers are negligible.

Insulin, that damn insulin

Insulin, the hormone so despised amongst laymen they would be willing to surgically remove their pancreas in order to stop to hormone production. What they are probably not aware of is the fact that in very short period of time they would lose any need for fats and carbs and protein. Not because they would finally conquer hunger but because they would be dead. With all other functions insulin has in the body, one of them is, yes, regulating fat storage. Many avoid food rich in carbohydrates believing they will get fat because of the spike in insulin, regardless of the quantity of food consumed. These people should ask themselves at least two questions:

  1. If insulin causes weight gain, and we know fats do not cause its production, does that mean we can consume infinite amounts of fats without the fear of getting fat? Where does their excess go?
  2. It has been long known, though often overlooked, that amino acids cause a strong insulin production. (1) If carbs make you fat because they produce insulin, does the same go for proteins?

The answers to these questions suggest that the stigma of insulin as „fat hormone“ is a completely wrong interpretation of its functions, which first and foremost include „directing“ the consumed nutrients after the meal. Insulin signals the body to use whatever it is that we ate as a source of energy. This way the body ensures the balance between stored carbs (glycogen) and fats. Carbohydrate and protein consumption causes a rise in insulin, which signals for their „consumption“ but also prevents using fats as an energy source. Fat consumption does not cause production of insulin so there is no inhibition in its consumption, and they can be used as primary source of energy.

Great, from now on I’ll eat only fats. Not so fast. There’s a few things to consider.

  1. The level of insulin production is very much dependent on total amount of consumed carbohydrate and protein. The body is not a switch machine. A small rise in its concentration will not lead to total nor permanent inhibition of fat consumption.
  2. This whole story is about acute processes which do not signal for a long-term fat storage. This is the responsibility of energetic balance in the body – the balance between calorie intake and consumption – which the body signals through other mechanisms. Regardless of weight gain and loss, the processes of gaining and „burning“ fat are interchanged throughout the day. The balance between these two through a longer time period determines whether we gain or lose weight, and it’s all consequential to the (im)balance of energy intake. I’m sorry, you do need to think about calories after all.
  3. Fat storage is possible without the presence of insulin. The hormone acylation stimulating protein (ASP) is the one responsible for that.

It’s time to stop blaming individual factors like insulin, leptin, ghrelin, any-hormone-in for weight gain, because this won’t change the laws of thermodynamics and it can only lead to wrong conclusions.

Is a calorie a calorie?

What even is a calorie? According to the definition, a (kilo)calorie is the amount of energy needed for a 1°C increase in temperature of one kilogram of water. Having that in mind, a calorie is a calorie, regardless of its origin – be it fat, carb, or protein. There are exceptions in cases of protein and fibers.

The calorie value of food is not equal to the energy that the body can metabolize (use for ATP production – the energy unit) or more specifically, use. While in the case of carbs and fats these two values are almost identical, the usable energy of protein is smaller than the total and is 3.2 and not 4 kcal/g. It’s similar with fibers, 1.4 instead of 2.0 g/kcal, and with alcohol, 6.3 instead of 7 g/kcal. In a practical sense, this difference does not play a significant role, but it can be emphasized in a high-protein or high-fiber diet. This is the main reason why some studies show a slightly higher weight loss in high-protein diets when compared to high-carb and moderate ones.

A completely different story is the nutritional value we get by consuming 1 kcal of a certain food – a so-called nutritive density. Due to difference in nutritive density, spinach is generally considered „healthier“ than sugar, because it ensures a higher nutritive value in the same calorie quantity. But regardless of that, a calorie is a calorie.

How to get fat from air?

By lying. Research unanimously shows that overweight people have a tendency to undervalue their calorie intake and overvalue their calorie expenditure. This leads to a supposed disproportion between body weight and calorie intake/consumption.

Why the concert about being overweight?

When explaining the BMI, we learned that excess weight is not a problem in itself. The problem is excess weight in form of fatty tissue. You thought obesity was only an aesthetic issue? You were wrong. Countless studies show negative effects of being overweight – high blood pressure, disrupted cholesterol levels, insulin resistance, inflammatory processes, and even some forms of carcinoma, to name a few. I won’t go any deeper because these mechanisms do not concern us at the moment.

In the next, and probably last, part of this small series on weight gain, I’ll explain a unique, incredibly simple, painless, and perfect way to lose weight. If you smell sarcasm, you’re correct.


  1. Floyd JC Jr, Fajans SS, Conn JW, Knopf RF, Rull J. Stimulation of insulin secretion by amino acids. J Clin Invest 1966; 45:1487–502.