Losing weight isn't usually pleasant. Obviously, disappearing centimetres and kilograms are satisfying, but they don't always compensate the discomfort connected with the amount of deprivations. Therefore, many people fighting against excessive body weight would like to solve their problem as fast as possible. As a result, those individuals undertake very aggressive actions, which... turn out to be inefficient or even dangerous. What wrong can happen during “fast slimming”?

There are plenty of articles on the negative results of fast slimming, however, it often happens that the core of a problem is presented in exaggerated way. It reminds frightening youths with the effects of taking drugs and creating arguments, such as: “if you try it once, you will get addicted for lifetime”. Although there are right reasons of such statements (drug addiction prophylaxis) and despite the fact that some part of people who “try” it get addicted, this problem does not concern everybody. Young people know that perfectly, so warning them is inefficient. How is it connected with the topic of this article?

It's the same thing with slimming

And it's also the same with warning against rapid slimming, because you can hear the statements, according to which if you cut down on calories too much, your body will start the “hunger mode” and metabolism will slow down so much that after two weeks of such diet you will gain weight after eating a loaf of bread with a piece of tomato. There are many similar theories and people on diet usually know they are untrue. And it's a short way to start believing that “everything negative they say about slimming fast is not true”. Whereas desperate slimming, even though it may not lead to “metabolic breakdown”, is risky and it usually does not cause the planned results. It can be even explained in logical way, avoiding the panic and fictitious arguments.

Clever biology...

The first thing you have to realise is the fact that human body has tried different ways of nutrition throughout the process of evolution. In fact, we don't remember that, but our genes – do. The history of our species is created with countless time intervals of the alternate phases of higher and lower availability of food. The conditions we experience nowadays are new for our biology. In the past we used to be simply hungry, even for days or weeks. And sometimes – months. Human body had to learn how to deal with it. It created the ability of economical use of energy during calorific deficit, as well as efficient sorage of reserves when the food is available. We have had these abilities until now, but nowadays the availability of food is unlimited – and that's an important change.

Hunger vs willpower

You have to remember about the fact that human body gets hungry during the deficit. Hunger gets stronger if the deficit is deeper and the longer it is (I won't write about some adaptation mechanisms connected with ketogenesis). In natural conditions, stronger feeling of hunger increased the motivation to look for and obtain food. Nowadays the physiological result is actually similar (we tend to look for food when hungry, e.g. we go outdoors to find a leaflet with and advert of a pizza place of burger house), but the metabolic result is different. Why is it different? Because the availability is high and we can store unlimited amount of energy in fatty tissue.

The body can defend itself

The information mentioned above is some kind of background for the idea of “fast slimming”. As human body has developed mechanisms, which let it adapt to low energy supply and, on the other hand, force us to look for and gain food stronger if the calorific deficit is stronger, it's good to remember that if you want to lose weight fast, you will notice fast response of the body. Agains appearances, however, the biggest problem is not the metabolic adaptation to lower energy supply (which is mainly manifested by the decrease of the spontaneous physical activity), but the feeling of hunger. Hunger is something we don't experience every day. It's not a “craving for a cake”.

Hunger and appetite

We have learned to mix hunger with appetite (and it's not the same thing). Appetite may even appear when you are full: for example after eating pizza you canfeel like having ice-creams or cheesecake. Hunger is when the body thinks it lacks food. Hunger is the feeling which can be really burdensome and... motivate to eating. It's hard to cope with real hunger in other way than by consumption. Moreover, the deeper energy deficit and the longer it lasts, the worse hunger (it's another simplification, because the quality of food products matters).


Therefore, the more rapidly you want to lose weight and the more extreme diet you use, the stronger the feeling of hunger and the more difficult it is to cope with it. We are usually able to deal with the increasing feeling of hunger for 2 -3 days. But day four is really difficult, besides, nobody's praising you and the progress is not as impressive as you wished. Day five is the peak when you crave for food. Day six comes with remorse and strong decision about improvement, but starting on... Monday. As a result, you please yourself for three days and then start dieting again, sometimes with better, other times worse motivation. But does it have to be like that every time? It doesn't, but it usually is. If someone thinks that such limitations don't concern him/her, in that case life usually verifies that enthusiasm quite fast, efficiently and... painfully.


Losing weight very fast is often doomed to failure. Unfortunately, whatever you imagine about the strength of the willpower, human body has proper instruments to force us to eat. That's why we should think about losing weight during reduction and remember that it's impossible to fix the negligence from the past months or years in few days or weeks.