#### II. Indication

1. Used in evaluation of Obesity

1. Highly correlated to body fat
2. May be best method available

1. Not accurate in muscular patients (athletes)
2. Not accurate in pregnancy or Lactation

#### V. Calculation

1. BMI = (weight in kilograms) / (height in Meters)^2
2. BMI = (weight in lbs x 700) / (height in Inches)^2
3. Approximating the weight at which BMI=27 (Obesity)
2. Add 5 pounds for every inch over 5 feet tall
4. Example: What weight is BMI=27 for 66 inch person?
5. Answer: 100 + (6x5) + 40 = 170 pounds

1. BMI <18.5: Underweight
2. BMI <20: Underweight or endurance athlete
3. BMI 20 to 22: Ideal Weight
4. BMI 22 to 25: Healthy Weight
5. BMI 25: Mild Obesity (WHO Grade 1, 110% Ideal Weight)
6. BMI 27: Moderate Obesity (120% of Ideal Weight)
7. BMI 30: Severe Obesity (WHO Grade 2, 130% Ideal Weight)
8. BMI 40: Morbid Obesity (WHO Grade 3)

#### VII. Interpretation: Boys (Derived from CDC BMI charts)

1. Approximation
1. Overweight BMI = (Age in years) + 14
2. Age 10
1. Mean BMI (50%): 17
2. At Risk BMI (>85%): 20
3. Overweight BMI (>95%): 23.5
3. Age 12
1. Mean BMI (50%): 18
2. At Risk BMI (>85%): 22
3. Overweight BMI (>95%): 25
4. Age 14
1. Mean BMI (50%): 19
2. At Risk BMI (>85%): 23
3. Overweight BMI (>95%): 27
5. Age 16
1. Mean BMI (50%): 20
2. At Risk BMI (>85%): 25
3. Overweight BMI (>95%): 29

#### VIII. Interpretation: Girls (Derived from CDC BMI charts)

1. Approximation
1. Overweight BMI = (Age in years) + 13
2. Age 10
1. Mean BMI (50%): 17
2. At Risk BMI (>85%): 20
3. Overweight BMI (>95%): 23
3. Age 12
1. Mean BMI (50%): 18
2. At Risk BMI (>85%): 22
3. Overweight BMI (>95%): 26
4. Age 14
1. Mean BMI (50%): 19
2. At Risk BMI (>85%): 24
3. Overweight BMI (>95%): 28
5. Age 16
1. Mean BMI (50%): 20
2. At Risk BMI (>85%): 25
3. Overweight BMI (>95%): 29

#### IX. Resources

1. NIH Obesity Education Initiative BMI Calculator
1. http://www.nhlbisupport.com/bmi/bmicalc.htm
2. CDC Growth Charts (source for childhood BMIs above)
1. http://www.cdc.gov/growthcharts
3. CDC Body Mass Index Information
1. http://www.cdc.gov/nccdphp/dnpa/obesity/bmi.htm

#### X. References

1. Green (1994) Bright Futures, NCEMCH, p. 266