How fast can you lose your fat?

Many people think they can lose a few pounds of fat with a crash diet in just a few weeks. Although this is not true, it is believed. The main reason for this is that people are falsely informed by vendors of supplements and diets. We are also all cheated with ‘before-and-after photos’ of people who claim to have lost a lot in a short time while in reality it has taken longer. What do you need to know to get a realistic view of this?


Nature knows certain boundaries everywhere. There is also a limit to the number of calories that you can get from your own fat mass per day. This appears to be connected to the number of kilos of fat you have. You can use about 70 kcal per day per kg of fat that you have , according to research ( source ). If you know that 1 gram of fat is 9 kcal then 70 kcal is 7.8 grams of fat. So you can lose a maximum of 7.8 grams of fat per day per kilogram of body fat. Below you will see a table in which you can quickly see what your fat mass is worth in terms of calories and fat to lose.

Losing weight is becoming less and less fast

The table above explains why you are losing less and less quickly. In the beginning, when you had 20 kilos of fat you could lose a kilo of fat every week, and now that you only have 14 kilos of fat you can only lose 750 grams. This is normal and healthy. A bodybuilder with a fat percentage of 8% can take a few weeks to lose a few hundred grams of fat to get 7% fat. Too fast and therefore losing weight is not an option for him. This comes again because the number of grams of fat you can consume is directly dependent on the number of kilos of fat you have.

That’s it!

Anyone who says that you can fall off faster than at this rate is either lying or means your lean mass and fluid. Your lean body includes your muscle mass and you do not want to lose. Moisture sometimes. Daily fluctuations in your weight are usually due to fluid and intestinal contents and not to fat. Do not be fooled by that.

The first kilos

When you just start with a caloric deficit, there is a good chance that you will start to use some stored energy in the muscles (glycogen). Adults can have about 400 grams of glycogen, depending on the muscle mass. Water is used when this glycogen is consumed. As a result, you also lose about 2 to 3 grams of water per gram of glycogen. This can therefore amount to a weight loss of about 1.5 kilos. This of course motivates but keep in mind that this is not fat, but glycogen and moisture. The rules in the table apply to losing fat.

Do not be too greedy!

As mentioned above by Herbals Daily, nature knows certain limits. There is also a limit to what you can eat less per day. What I do not want is that as a reader with 30 kilograms of fat you think you can eat 2100 kcal less per day (or can consume with sports). Your body functions best when you eat at least the number of kcal of your basic metabolism. If you want to sit down there, I recommend doing this under supervision. Feel free to contact me if you want customized advice.