A BMI between 18.5 and 24.9 is categorized as normal. Less than 18.5 is underweight, greater than 25 is overweight, and greater than 30 is obese. A BMI that is greater than 40 (the top right part of the chart) is morbid obesity (Lewis, 2014, pp. 906).
As I discussed in my first post, BMI does not always accurately represent a person's body fat content or health risks. A muscular athlete usually weighs more than a normal person of their height, and so their BMI may indicate that they are overweight or obese. My father's BMI would classify him as obese, but he has low to normal blood pressure and is in good health. BMI may underestimate obesity in elderly people, because they have decreased overall body mass. Despite these inaccuracies, BMI is still the most used categorization of body weight.
Other measures of obesity-associated health risks include waist circumference and waist-to-hip ratio. Both of these measures reveal the distribution of fat in the body. Visceral fat in the abdominal cavity is increases health risks more than subcutaneous fat. Simple assessment of body shape can often reveal distribution of fat - gynoid (pear) shape is associated with a better prognosis than android (apple) shape (Lewis, 2014, pp. 907-908).
Children have a slightly different categorization of weight. "Overweight status is defined as an age- and gender-specific body mass index (BMI) between the 85th and 94th percentile based on the 2000 Centers for Disease Control and Prevention Growth Charts for the United States. Obesity is defined as an age- and gender-specific BMI at or above the 95th percentile for children of the same age and sex" (Hockenberry, 2015, pp. 728).
Lewis, S. L. (2014). Obesity. In Harding M. M. (Eds.), Medical-Surgical Nursing - Assess and Management of Clinical Problems. (pp. 906 - 922). St. Louis, Elsevier.
Hockenberry, M. J. (2014) Health Problems in the Adolescent. Wong's Nursing Care of Infants and Children. (pp. 727 - 737). St. Louis, Elsevier.
Great article
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