There is a good percentage of the population that is very unfamiliar with what a Bass Mass Index (BMI) is. They don't realize how important this index is to their overall health. The BMI index is what doctors use to determine a persons body fat or health percentile ranking. By using a BMI calculator they can measure a person overall body weight and fat density.

The process doesn't measure the body fat directly, however the measurement does correlate with a direct measure of body fat. Using a BMI measurement is considered very inexpensive and easy compared to the alternative of paying a company to perform a direct body fat test.

The BMI index uses a person weight and height to determine their overall health percentile ranking. The ranking is age and sex-specific, and not just a genetic reading. After combining a person age and weight, the BMI calculator assigns a number to different categories. The categories are than ranked by levels such as; underweight, healthy weight, overweight and obese. The BMI calculator is not a diagnostic tool, but a gage on a person's morbidity and/or mortality risk. A doctor will be able to gage if a person weight poses a health risk.

Patients who are classified under the underweight ranking have just as much of a possibility of developing health issues as those who fall under the overweight and obese categories. It just more common to see an overweight patient with health programs than an underweight.

The BMI index was created between 1830 and 1850 by the Belgian polymath Adolphe Quetelet. They were in the process of developing "social physics" when they realized what they had developed was a way to calculate body mass. At the time of development a BMI calculator wasn't considered to be of much use. During that time your body mass wasn't link to the number of diseases it is today. Today we understand that obesity can be linked to heart, liver and many bring upon the onset of other diseases such as Diabetes. You BMI can also effect whether or not you qualify for health and/or life insurance. From a health practitioner's point of view, your BMI is something you want to work with your doctor to keep under control.