|>>|| No. 4968
People accumulate fat differently depending on their genes. Some people mostly have subcutaneous fat, so they have a relatively low risk of obesity-related disease even if they're quite overweight. Conversely, some people with just "a bit of a gut" are at relatively high risk, because it's all visceral.
A waist size of over 37" means that you're at high risk of diabetes and coronary disease, even if you're not particularly fat elsewhere. The classic beer belly is a serious warning sign, even if you're relatively slim everywhere else.