Very often dieters have no idea, apart from the number on the scales, how their body is reacting to a low-calorie diet and physical activity: are we losing fat or lean mass or just liquids? 
In fact, sometimes the scale drops drastically and then rises easily, and this is the sign that our weight loss was mostly a loss of water (a typical symptom of light diets); other times the scale does not move even with the most holy hand, we are dejected but in reality our body composition is changing, we are gaining lean mass and disposing of fat (typical diet and gym situation).

How to tell if our diet is making us lose body fat, in short?
From today Levl will tell us, a very simple device to use, which detects the concentrations of acetone in our breath : these concentrations are a signal to understand if our body is disposing of body fat or not.
Basically Levl is a machine to breathe into. A similar device was developed by Toshiba in 2014 , in this case it is a model aimed at picking up the signals that the body is in a position to lose body fat., through a precise data on the concentration of acetone. Of course, the device does not limit itself to analyzing whether we suffer from acetonemia, but to ascertain that the levels of acetone in our breath are within a certain range, positively correlated to the loss of fat mass.

But how does it work to lose weight? Simple, the Levl determines if our body is using the fat reserves for energy purposes: it can be used every day to test the diet and its results, but also to understand if a certain variation in diet or physical activity is right for us. making you lose body fat or not.

The problem at the moment is the cost, prohibitive: Levl costs around 700 dollars and needs a monthly maintenance of around 50 dollars. It is also only available in the United States, but should soon arrive in Europe, hopefully at more competitive costs. The Pro version is designed for personal trainers or nutritionists / dieticians who want an assessment tool for their patients on a diet; the home version for those who want to monitor themselves.