What does it mean to be severely obese?

Approximately about 100 pounds overweight for men and 80 pounds overweight for women.

Improved answer.

Again, the above answer is unfortunately completely wrong.

First, we need to determine what is to be considered "overweight" versus "obese." We begin by looking into Body Mass Index (BMI), which is a measurement of height and weight. As height is part of the equation, pounds alone cannot determine who is normal weight versus who is overweight or obese. Criticism of using BMI to determine obesity involve the fact that BMI does not actually measure the amount of body fat per person. Therefore, someone who has a large bone structure and muscular will have a higher BMI even if he or she has very small amounts of fat deposits.

Still, BMI is the general clinical method used to determine who is underweight, normal weight, fat or obese. With this method:

• A person with a BMI between 25 kg/m2 and 30 kg/m2 is considered overweight.
• A person with a BMI over 30 kg/m2 is considered obese.

From here, we have different categories or "classes" or obesity:

• Obese Class 1 is a BMI range of 30 to 35 kg/m2.
• Obese Class 2 is a BMI range of 35 to 40 kg/m2.
• Obese Class 3 is a BMI range of over 40 kg/m2.

To answer your question:

• "Severely obese" refers to Class 2 obesity.
• "Morbidly obese" refers to Class 3 obesity.
• There is even a "super obesity", referring to those with a BMI between 45 and 50.

Therefore, we cannot assume that it takes "100 pounds" for a man or "80 pounds" for a woman to be "severely obese". We must look at their height as well to determine their BMI.

You didn't ask but I would like to point out that these numbers do not refer to overweight or obese children. While BMI in children is calculated the same, healthy weights for children are determined by measuring the child's BMI and comparing it to typical values of children within the same age and height range.

You also didn't ask but I'd like to point out that nonsmokers with a BMI between 20 and 25 usually have the lowest rates of mortality among their age group. Among those who smoke, those with the same 20-25 BMI also have lower rates of mortality than other smokers in their age group. On the other hand, obesity reduces life expectancy by 6 to 7 years on average. "Severe obesity" reduces life expectancy by 10 years.