How do I know if my child is overweight?

How do you know if your child is overweight? Along with your pediatrician’s judgment, a good indicator is your child’s body mass index, or BMI. This number is based on your child’s height and weight. If your child has a BMI higher than 95 percent of other kids in the same age, sex, and height group, that’s considered obese. There are a number of websites that will automatically calculate your child’s BMI if you punch in a little info. (Try this one: apps.nccd.cdc.gov/dnpabmi. Hint: Don’t use an adult BMI calculator; the formula is different for children.) If doing math tickles you, however, you can figure out your child’s BMI with these steps:

1. Measure your child’s weight in pounds.
2. Measure your child’s height in inches, and multiply that number by itself (if he’s 58 inches tall, that would be 58 × 58, which equals 3,364).
3. Divide your child’s weight by the figure you just calculated in step 2.
4. Multiple the resulting figure by 703.

For example, if your seven-year-old son weighs 80 pounds and is 4 feet 10 inches tall (58 inches), your calculation would look something like this:

58 × 58 = 3,364

80 ÷ 3,364 = .0238

.0238 × 703 = 16.72

BMI = 16.72

By looking at the boys’ BMI chart found at www.cdc.gov/growthcharts/, your son’s BMI of 16.72 falls in the seventy-fifth percentile, which means he’s a normal, healthy weight.

From The Smart Parent's Guide: Getting Your Kids Through Checkups, Illnesses, and Accidents by Jennifer Trachtenberg.