The Body Mass Index (BMI) is the mathematical formula used to determine your degree of overweight or obesity. The BMI measures your weight, taking your height into account.
To calculate your BMI using the metric system, you divide your weight in kilograms by your height in meters squared.
or
To calculate your BMI using pounds and inches, you divide your weight in pounds by your height in inches squared then multiplying your result by 705.
Having:
a BMI of less than 18.5 means that you are underweight and medically at risk
a BMI of 18.5 to 24.9 means you have a healthy weight
a BMI of 25 to 29.9 is classified as being overweight
a BMI of 30 or above is classified as obesity
a BMI of 40 or above is termed morbid obesity
Your Healthiest Weight Range
To determine your ideal weight range you need to know your BMI as well as your waist/hip ratio. (See Body Shape page)
The Ideal Weight Range: When your BMI is between 19 to 22 and your Waist/Hip Ratio is between .70 to .775
A Safe Weight Range: Having a BMI between 19 to 25 and a Waist/Hip Ratio between .70 to .80
A Risky Weight Range: Having a BMI between 25 to 30 and/or a Waist/Hip Ratio between .80 to .90, and
The Danger Weight Range: Having a BMI greater than 30 and/or a Waist/Hip Ratio greater than .90
By knowing and using your BMI and your Waist/Hip Ratio together, you can easily see whether you need to trim a few pounds or inches.