Obesity Defined
The simplest definition of obesity is an excessive amount of body fat. Obesity is not the same as being overweight, which refers to an excess of body weight relative to height. For example, a muscular athlete may be overweight, yet have a low body fat percentage. With this distinction in mind, it is obvious that using body weight alone as an index of obesity is not entirely accurate. The body mass index (BMI) is now the accepted standard for classifying individuals with regard to body composition. BMI generally correlates well to a person’s total body fat.
A BMI between 25 and 29.9 is a marker for being overweight, while obesity is identified by a BMI of 30 or greater. A BMI of 40 or greater is referred to as morbid obesity and is associated with extreme health risks. Example: a 5’4” woman with a BMI of 30 is about 30 pounds above her ideal body weight. So, obesity is not a matter of simply being a few pounds overweight. It reflects a significant amount of excess fat.
Waist size is also important for determining overall health. The combination of your BMI and your waist circumference is very good indicator of your risk for all of the diseases associated with obesity, especially the major killers like heart disease, strokes, cancer, and diabetes.