Excess weight increases your risk for many diseases including stroke, type 2 diabetes, high blood pressure and heart disease. Finding out if you are overweight can be done with the help of the body mass index (BMI) formula. Your BMI is a number that indicates whether you are underweight, normal weight, overweight or obese. Because you don't need any fancy equipment to determine your BMI, the formula is easy and affordable to calculate.
Things You'll Need
- Measuring tape
Stand on a scale to determine your current weight in pounds. Write down this number.
Measure how tall you are and calculate your height in inches squared. One foot equals 12 inches. For example, if you are 5 feet and 7 inches tall, multiply 5 feet by 12 and add the 7 inches to get a total of 67 inches. Multiply 67 inches by 67 inches to get 4,489 inches squared. Record this number.
Take your weight in pounds and divide this by your height in inches squared. Multiply the result by 703. If you weigh 150 lbs. divide this by 4,489 and multiply the result by 703 to get a BMI of 23.49.
Interpret your result. If your BMI is below 18.5 you are considered underweight; a BMI between 18.5 and 24.9 means you are of normal weight; a BMI between 25.0 and 29.9 translates to being overweight and a BMI of 30.0 and higher means you are considered obese. A BMI of 23.49, as per the example, is considered normal weight.
Measure your waist circumference to get a more accurate indication whether you are overweight. If you are very muscular your BMI will be high but this doesn't mean that you are overweight. Measuring your waist can therefore be done in addition to calculating your BMI. Drape a tape measure around your waist starting at the top of the hipbone and going all the way around across the belly button. A female with a waist circumference greater than 35 inches has excess belly fat and is at an increased risk for diseases. A male with a waist circumference greater than 40 inches is in the same predicament.