Why does someone who weighs 81 pounds have a fat abdomen?

Answer 1

Starting from the premise that you understand that 81 pounds is not overweight for the person (based on height), the next question becomes, "is it a fat abdomen?"

Probably not.

In fact, many people who are UNDERWEIGHT are also in poor physical condition. A bulging abdomen is most likely caused by poor muscle tone. Many people who are underweight think that it's a good thing, but it's not. Often underweight people sacrifice muscle mass for lower weight.

What holds in the intestines? Your abdominal muscles.

The person with the bulging abdomen needs to eat rightAND exercise.