# Is BMI an accurate predictor of health and obesity?

BMI is an index used to predict health and obesity. As you probably know, this index is a mathematical formula that is calculated using weight and height. You can calculate this number using our BMI calculator.
Some experts use this index to determine the amount of extra fat or health of people. In this way, if BMI is higher than 25, They suggest to lose weight. But in our experience, there are some people who have a BMI higher than 25, but there is no need to lose weight! In the rest of this article, we will discuss about this issue and answer the question of whether BMI is an accurate predictor of health and obesity or not!

As we said on our BMI calculator page, the formula for calculating this index is based on weight and height. This formula is as follows:

BMI = weight / [height] ^ 2

With a little attention, you will notice that only height and weight are used in this Formula. But there is nothing about body fat percentage, muscle mass, bone density, amount of water stored in the body and other factors.

A person may have high weight due to high muscle mass, but have a good amount of fat and do not need to lose weight. For this reason, we and many experts believe that BMI is not an accurate predictor of health and obesity most of the time.

In the following, we will discuss an example in this regard so that you can understand it better. At the end, we will discuss about two better indexes to predict health and obesity.

### Consider this example

BMI of an 85 kg man with a height of 180 is equal to 26. If we follow the criteria of this index, this man is overweight and should lose weight, but he doesn’t need to lose weight! This information is related to a male bodybuilder with a body fat percentage of about 17, who has high muscle mass. Some nutritionists suggest to this person that he should lose weight according to the amount of BMI, but this is not logical at all.

### BMI index works correctly for some people

Contrary to the example we gave, BMI can work correctly for some people. Those who do not have high muscle mass can use the relationship between weight and height to diagnose health and obesity.

For example, in the same example above, If we assume that this man does not have a high muscle mass, the BMI index guessed correctly and he needs to lose weight. But when a person has high muscle mass, because it is not clear whether this weight is due to fat or muscle or water stored in the body, then BMI does not work properly.

But for people who do not have high muscle mass, it is very likely that their weight has increased due to fat storage. However, despite all this, we still recommend you to use other indexes in addition to BMI.

### What is the best scale for predicting health and obesity?

So far, we have found that BMI index does not provide accurately predict health and obesity in some cases. In this section, we provide some better indexes to identify these cases.

#### Body fat percentage

The reason for obesity and endangering health is the fat stored in the body. So if we want to provide a better index instead of BMI, we can refer to body fat percentage. Body fat percentage is the percentage of your body that consists of fat.

According to a study, the healthy fat percentage range for men is between 12 and 20 percent. This range for women is between 20 and 30 percent.

#### Muscle mass

There are some men or women who are so thin that they are still at risk of disease. These people have a very low percentage of fat. So if we want to consider only the body fat percentage, we may forget this group. Another measure that is important to us is muscle mass.
Many extremely thin people or those who are old lose a lot of muscle mass for several reasons. So we should consider muscle mass two. One of the ways to build muscle or protect of muscles is resistance training. So don’t let muscle loss happen under any circumstances.

#### The best solution is to use all indexes

The best way to predict health and fitness level is to use all three indexes. You can use BMI, body fat percentage and muscle mass to make the best decision.

Posted

in

by

Tags: