The body mass index (BMI) is a tool that is used to asses health risk based on weight and height. Each height has a different healthy weight range, above which, risks of certain conditions such as heart disease, strokes and diabetes increase.
What is BMI for?
BMI is a great tool for assessing the health of a large population such as an entire city. The data needed to calculate BMI is easy to come by (weight and height) and can be figured out in seconds. BMI can be used for these large populations because it is based on an average person.
If you use BMI on a single person, he or she might not fit into the mold of an average person. They might be more muscular or have a bigger or smaller frame. While BMI shouldn't be used as the only guide to figuring out an ideal weight, it can be a good starting point. BMI is simple and quick to use so you'll get an idea of where you stand in seconds.
Once you figure out your BMI, you will be placed in a weight category: underweight, normal, overweight or obese. If you are in the obese category, you need to make a change in your life. If however, you're borderline overweight, you can also test your body fat percentage to get a better idea of where you stand.
If you're overweight on both scales, a lifestyle change is in order. If you're normal according to your body fat percentage, BMI might not be a good measure for you.