Obesity is a disease of excess fat storage, but people store fat differently. Central obesity, or obesity around your mid-abdomen is actually the most dangerous kind. So one thing we like to do in the office is measure a patient's waist circumference, to see if they're at risk for some of the other illnesses that go along with central obesity.
The way to do this is you can take a tape measure, and you measure your circumference, starting at the highest point of your hipbones. So in men, if the number is greater than 40 inches, then you're considered to have central obesity. In women, the number is 35 inches. Another way to determine whether you're obese by using a tape measure is to measure your waist to hip ratio.
The way to do that is take your tape measure and measure the narrowest part of your waist, then you're going to divide that, by the number you get when you measure the widest part of your hips. In men, if the number is greater than one, you're considered obese, and in women if it's greater than 0.8, that's considered to be obese.
So remember that people store fat differently and so, if you do calculate that you have a healthy waist circumference, but you still think that you might be obese, or your BMI comes out to a number that considers you obese, you still need to take that seriously and try to make the necessary changes to lose weight, so that you can become healthier.