Several other terms are used in the medical literature to define and classify excess weight. They have not been fully standardized. They revolve around the BMI and are included in Table.
Terms used to define and classify excess weight.
BMI Classification Other Terms
< 18.5 Underweight
18.5 to 24.9 Normal
25 to 29.9 Overweight
30 to 34.9 Obese—Class I
35 to 39.9 Obese—Class II
> 40 Obese—Class III Severe Obesity
40 to 40.9 Morbid Obesity
> 50 Super Obesity
So morbid obesity, super obesity, or severe obesity rep-resent the patient with the heaviest weight and the greatest risk of severe health problems. “Morbid obe-sity” is an old term and tries to capture the idea that this excess weight is a risk to health and may even be life threatening.