Lean mass and fat mass

Although many nutritionists and dieticians have at their disposal a set of tools and useful elements to know the weight of a person (a good example of this is the IMC calculator), always know the body weight of a person can lead to deceit.

This is because the most basic tools that a nutritionist has sometimes can not clarify in what percentage the fat of a person is distributed, whose diet may depend on the volume or percentage of fat that the patient has.

For this reason, it is advisable to know the Differences between lean mass and fat mass.

Main differences between lean mass and fat mass

What is lean mass?

The Lean mass is made up of internal organs, muscles and bones. In this sense, muscle mass in men tends to represent approximately 45% of their weight. While, in women, their muscle mass reaches only 35% of their weight.

Defining it in a more concrete way, we can say that lean mass is the whole mass of our body that is not fat, being able to be not only bone, but also muscles and other tissues (such as organs, for example). That is to say, is the fat-free body mass.

It is, for example, something very important for the bodybuilder or for the person who practices fitness, since its goal is to try to lose weight while maintaining or increasing your own lean mass, being a useful indicator to discover that muscle mass is It has remained the same - or has increased - while losing fat.

What is fat mass?

Unlike lean mass, the fat mass is that formed mainly by structural and deposit greases. In man, it reaches 12% deposit fat and 3% structural fat. While, in women, its deposit fat rises up to 14%, and structural fat reaches 12%.

But it is not the same to talk about average of fat and the body mass index. And is that in the case of fat mass corresponds to the fat cells, while as indicated above, lean mass corresponds among other aspects to the muscles.

To measure the percentage of body fat different methods are used:

  • Measurement of a skinfold, measuring the thickness of a clamping of the skin in different parts of our body. It is useful to know subcutaneous fat.
  • Bioelectrical impedance, through which an electric current is passed through the body, so that its resistance is linked to the rate of fat.

In addition to these two tools it is also possible to use an empirical formula derived directly from the Body Mass Index (BMI), providing the possibility of calculating the body fat percentage (PGC). However, it is a useful formula only for people between 15 and 50 years of age.

What is it useful to know the fat and lean mass of a person?

For a dietitian it is extremely useful to know how much lean mass and fat your patient has, given that the goal is to elaborate an appropriate diet to lose fat mass, avoiding the least possible loss of lean mass.

To do this, it is essential that the diet has an adequate content of foods rich in protein and carbohydrates. Of course, the latter should only provide the calories that the body needs each day, to avoid consuming muscle as a source of energy. This article is published for informational purposes only. You can not and should not replace the consultation with a Nutritionist. We advise you to consult your trusted Nutritionist.

How to calculate lean body mass and body fat percentage (October 2019)