Body mass index, or BMI, is a measure of body fat that allows health care providers to predict potential weight problems in teenagers. Because teens experience frequent growth spurts and height and weight ranges can vary significantly from month to month, BMI is the best way to check for indicators that a teen might be overweight or obese. The Centers for Disease Control and Prevention (CDC) recommend that teens check their BMI annually through age 19. It's an easy process to calculate BMI for teenagers.
Step 1
Have your teenager weigh himself using the scale. Write down his weight in pounds.
Step 2
Use the tape measure to measure the teenager's height. Write down her height in inches.
Step 3
Multiply your teenager's weight by 703, using a calculator.
Step 4
Divide the total by your teen's height.
Step 5
Divide that total again by your teen's height. (For example, if your teenager is 5 feet tall and weighs 100 pounds, multiply 100 x 703 to get 70,300. Divide 70,300 by 60 inches---the number of inches in 5 feet---to get 1,171.67. Then divide 1,171.67 by 60 again to get 19.53. That's your teen's BMI.)
Step 6
Evaluate your results. Use the CDC growth chart---you can download the right one for your child by clicking on Growth Charts under Resources below---to compare your child's BMI to the standards for obesity. Teens are considered underweight if their BMI falls into the fifth percentile or lower on the chart; normal weight if their BMI falls between the fifth and 85th percentiles; overweight if their BMI is between the 85th and 95th percentile; and obese if their BMI is at the 95th percentile or higher.
Tips and Warnings
- To convert feet to inches for your calculations, multiple the number of feet by 12. Then add any additional inches to that total. (If your teen is 4 feet 8 inches tall, you'd multiply 4 feet times 12 to get 48 inches, then add the remaining 8 inches for a total of 56 inches.)
- If your child's BMI number indicates a weight problem, talk to your health care provider about healthy ways for your child to achieve a healthy weight. Childhood obesity is a growing problem according to the CDC, but early intervention can help prevent serious health problems.
Things You'll Need
- Scale
- Paper
- Pen
- Tape measure
- Calculator
Member Comments