Not to be confused with BMR, Body Mass Index, abbreviated as BMI, is the calculation of a person’s body fat in relation to that person’s height and weight. BMI is a person’s body weight divided by the square of their height – here is a link to a free tool for calculating BMI.
BMI can also be found by finding your height and weight on a chart. In this form, the chart displays the weight on the horizontal axis and the height on the vertical axis. Where the two intersect, your BMI can be determined and placed into the appropriate BMI category
BMI is typically used to determine if an adult has a weight issue that needs to be dealt with. However, body mass index is just a first step to determine if more tests and screenings need to be facilitated.
For example, there could be two men who are both around six feet tall and weigh two hundred pounds. The first male could be slightly overweight and not exercise frequently, therefore the BMI indicated for this individual will probably be accurate and necessary steps to lower his BMI should be taken.
However, if the second man works out six or seven days a week, his percentage of body fat is not being taken into consideration. Since muscle will weigh more than fat, his weight is the same as the man who is not in shape, but their BMI’s are the same because the percentage body fat of the weight cannot be determined in the BMI formula.
This displays the need for further tests and methods for determining health risks because the second man could be very healthy but his BMI would not indicate this.
There are four main categories of BMI:
- First, those with a BMI under 18.5 are considered underweight.
- Next, people are described as normal or average with a BMI in between 18.5 and 24.9.
- An overweight status is between 25.0 and 29.9.
- Finally, any BMI over 30.0 is classified as an obese body mass index.