Obesity means having far too much body fat. It's about much more than your clothing size or how you look. It can seriously affect your health.
Your whole body feels it, from your joints to your heart, blood pressure, blood sugar, and other systems. The extra fat cells produce inflammation and various hormones, which boosts your odds of chronic medical conditions.
If it seems like those odds are stacked against you, remember that it's possible to beat them. The first step is to know where you stand.
Are You Obese?
If your doctor says you're overweight, that means "you're slightly over what's considered healthy," says Y. Claire Wang, MD. She's co-director of the Obesity Prevention Initiative at Columbia University.
Obesity is beyond being simply overweight. It's very common -- more than 1 in 3 U.S. adults are obese. If you're one of them, you can work to lose weight. Although it's not easy, dropping some of those extra pounds -- maybe fewer than you think -- starts to turn things around for you.
What Your BMI Says
For adults, experts usually define obesity based on body mass index, or BMI. This formula relates your weight to your height.
For instance, if two people weigh the same amount but one is taller than the other, the taller person will have a lower BMI. To find your body mass index, plug your height and weight into a BMI calculator.
If your BMI is:
- Below 18.5: underweight
- 18.5-24.9: normal
- 25-29.9: overweight
- 30 or higher: obese
If you're obese, your doctor might talk about the categories of obesity:
- Obesity level l: BMI of 30-34.9
- Obesity level ll: BMI of 35-39.9
- Obesity level lll: BMI of 40 or higher, which some also call "morbid" obesity