NOTE: It is important to have your doctor perform regular BMI measurements for your child so the doctor can discuss the results with you.
BMI is calculated the same way for both adults and children. The calculation is based on the following formulas:
Formula and Calculation
Kilograms and meters (or centimeters)
Formula: weight (kg) / [height (m)]2
With the metric system, the formula for BMI is weight in kilograms divided by height in meters squared. Since height is commonly measured in centimeters, divide height in centimeters by 100 to obtain height in meters.
Example: Weight = 68 kg, Height = 165 cm (1.65 m) Calculation: 68 A- (1.65)2 = 24.98
Pounds and inches
Formula: weight (lb) / [height (in)]2 x 703
Calculate BMI by dividing weight in pounds (lbs) by height in inches (in) squared and multiplying by a conversion factor of 703.
Disabled World also provides a number of informative articles and information relating to Childhood Obesity
Child Obesity Awareness Information
The color of the obesity, including childhood obesity, awareness ribbon is yellow. The month of September is National Childhood Obesity Awareness Month - President Barack Obama proclaimed September as National Childhood Obesity Awareness Month, encouraging Americans to help our youth lead more physically active lifestyles and make healthier food choices. Childhood obesity has increased more than fourfold among those ages 6 to 11. More than 23 million children and teenagers in the United States ages 2 to 19 are obese or overweight.
BMI can be used for population assessment of overweight and obesity. BMI is generally regarded as a satisfactory tool for measuring whether sedentary individuals are underweight, overweight or obese with various exceptions, such as: athletes, children, the elderly, and the infirm.
BMI is proportional to mass and inversely proportional to the square of the height. So, if all body dimensions double, and mass scales naturally with the cube of the height, then BMI doubles instead of remaining the same. This results in taller people having a reported BMI that is uncharacteristically high, compared to their actual body fat levels.
BMI is interpreted differently for children and teens, even though it is calculated using the same formula as adult BMI. Children and teen BMI needs to be age and sex-specific because the amount of body fat changes with age and the amount of body fat differs between girls and boys.
Obesity among 2- to 19-year-olds is defined as a BMI at or above the 95th percentile of children of the same age and sex in this 1963 to 1994 reference population. For example, a 10-year-old boy of average height (56 inches) who weighs 102 pounds would have a BMI of 22.9 kg/m2. This would place the boy in the 95th percentile for BMI - meaning that his BMI is greater than that of 95% of similarly aged boys in this reference population - and he would be considered to have obesity.
A BMI that is less than the 5th percentile is considered underweight and above the 95th percentile is considered obese. Children with a BMI between the 85th and 95th percentile are considered to be overweight.
Recent studies in Britain have indicated that females between the ages 12 and 16 have a higher BMI than males of the same age by 1.0 kg/m2 on average.
The prevalence of adult BMI greater than or equal to 30 kg/m2 (obese status) has greatly increased since the 1970s. Recently, however, this trend has leveled off, expect for older women. Obesity has continued to increase in adult women who are age 60 years and older.
BMI generally overestimates adiposity on those with more lean body mass (e.g., athletes) and underestimates excess adiposity on those with less lean body mass.