Healthy Eating & Diet
Obesity - Overview
What is obesity?
Being obese means having so much body fat that your health is in danger. Having too much body fat can lead to type 2 diabetes, heart disease, high blood pressure, arthritis, sleep apnea, and stroke.
Because of these risks, it is important to lose weight even if you don't feel bad now. It is hard to change eating habits and exercise habits. But you can do it if you make a plan.
How do you know if you are obese?
You can use a
measurement called a body mass index, or BMI, along with your waist size 
, to decide whether your weight is
dangerous to your health. The BMI is a combination of your height and weight.
If you have a BMI of 30 or higher, your extra weight is putting your health in
danger.
Use the
Interactive Tool: Is Your BMI Increasing Your Health Risks? 
to check
your body mass index.
Use the Interactive Tool: What Is Your Child's BMI? to check BMI in children ages 2 to 19.
People who carry too much fat around the middle, rather than around the hips, are more likely to have health problems. In women, a waist size of 35 in. (88 cm) or more raises the chance for disease. In men, a waist size of 40 in. (101 cm) or more raises the chance for disease.1
If you are Asian, your health may be at risk with a BMI of 27.5 or higher. Also, health problems are seen with a smaller waist size. In Asian women, a waist size of 32 in. (80 cm) or more raises the chance for disease. In Asian men, a waist size of 36 in. (90 cm) or more raises the chance for disease.2
Check this table to find your risk for disease using your body mass index and waist size.
What causes obesity?
When you take in more calories than you burn off, you gain weight. How you eat, how active you are, and other things affect how your body uses calories and whether you gain weight.
If your family members are obese, you may have inherited a tendency to gain weight. And your family also helps form your eating and lifestyle habits, which can lead to obesity.
Also, our busy lives make it harder to plan and cook healthy meals. For many of us, it's easier to reach for prepared foods, go out to eat, or go to the drive-through. But these foods are often high in fat and calories. Portions are often too large. Work schedules, long commutes, and other commitments also cut into the time we have for physical activity.
You've tried diets, but you always gain the weight back. What can you do?
WebMD Medical Reference from Healthwise
Obesity Topics
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