How do you determine a healthy BMI for a teenager?
HOW DO YOU CALCULATE BMI FOR A TEENAGER?
Both age and gender are taken into account when calculating the BMI (Body Mass Index) for a teenager; age because the body fat changes with age, gender because the amount of body fat is different between boys and girls.
You will need to obtain accurate height and weight measurements from the teen being measured. The easiest way from here is to consult an online BMI calculator. The Center for Disease Control has one at their site, here: http://www.cdc.gov/healthyweight/assessing/bmi/. However, if you wish to do the math yourself, there are five steps involved.
1) First, get the subject’s weight. Say we have a young lady of 115 pounds.
2) Second, get their height. Our teen is 5’3", or 63 inches. Now we need to square that (multiply it by itself). 63 squared is 3,969
3) Now divide her weight (in pounds) – 115, by her height (in inches, squared) – 3,969 . This equals a rounded 0.029.
4) Take 0.029 (our teens weight divided by her squared height) and multiply it by 703. 703 is the conversion factor we use to calculate BMI. (I do apologize but I was unable to discover what makes 703 this magic number!) This gives us 20.3.
5) Consult a reputable site for a BMI graph and guidelines for appropriate BMI for your Teen’s age and weight. A couple are listed below. General guidelines according to the Dietary Guidelines Advisory Committee are: BMI from 18.5 to 25 – Healthy, BMI from 25 to 30 – Overweight, BMI over 30 – Obese
http://www.health.gov/dietaryguidelines/dga2000/document/aim.htm
http://kidshealth.org/teen/food_fitness/dieting/bmi.html (This one does it ALL for you! – well you do have to have your own scale and measuring tape!)
*Note* An unhealthy BMI can always be changed! Remember that the BMI is just an indicator and as such can be used to help you work on changing your life for the better as you add exercise and healthy eating habits into your lifestyle.
