A person is considered obese when his or her weight is 20% or more above normal weight or his or her body mass index (BMI) is over 30. "Morbid obesity" means that a person is more than 100 pounds over normal weight or has a BMI of 40 or higher. Follow the links below to find WebMD's comprehensive coverage about obesity, its causes, treatment, and much more.
Obesity and When to Seek Help
WebMD explains obesity and how to take steps to lose weight.
Health Risks of Obesity
Being overweight or obese puts you at risk for many serious health conditions, including diabetes, sleep apnea, and even cancer. Learn more from WebMD about diseases you can prevent by losing weight.
What Your Doctor Really Wants You to Know About Weight Loss
Your doctor said it’s time to lose weight, but you’ve still got questions. Here are answers.
What Is Ovarian Cancer? What Causes It?
Learn more about what might raise your odds of getting ovarian cancer, and some ways you might be able to lower those odds.
Am I Obese? How Experts Define What Obesity Is
Do you know the difference between being overweight and being obese or morbidly obese? Find out what obesity definitions mean, what causes obesity, and how it's treated.
Helping Your ‘Not-Thin’ Kids
Fit kids come in all shapes and sizes, just as fit adults do. And many experts say we should keep this foremost in mind when it comes to children who aren't thin, but who eat healthfully, have lots of energy, and exercise almost every day.
Weight Loss Stories: How 6 People Shed the Pounds
When you're working on weight loss, it can help to have a little inspiration. Here, six people share their secrets on how they lost the pounds.
12 Tips to Lose the Weight for Good
Feel like you’ve tried every diet trick in the book? Here are 12 new weight-loss strategies to try.
Losing Weight and Keeping It Off
An expert discusses diet, exercise, mental preparation, and rapid weight loss.
The Rise in Obesity
Why is the rate of obesity on the rise?
When Being Overweight Becomes a Health Problem
Jonathan Sackner Bernstein, MD, talks about when being overweight becomes a health problem.
The Importance of Diet and Exercise in Reducing Obesity
Being overweight is a risk factor for diabetes, heart disease, and maybe even cancer. Learn how weight affects your body.
Slideshows & Images
Slideshow: Surprising Reasons You're Gaining Weight
What are some possible causes of sudden weight gain, when there are no changes in diet or exercise? Learn about the effects of certain medications, some medical conditions, sleep issues, and more.
Slideshow: 17 Tips to Lose 100 Pounds or More
These lifestyle changes -- suggested by experts and real people who've lost the weight -- can help you stay on the path toward a healthier body and a happier you.
Can't Wait for the Future? Try These Weight Loss Tips Now
Slideshow: Surprising Things That Hurt Your Liver
Alcohol and acetaminophen are well-known liver dangers, but what else can be harmful? Some of them may surprise you.
Fat Facts Quiz: Test Your Knowledge
Test your diet IQ with this quiz about different types of fat and fats.
Quiz: Test Your Nutrition IQ
Take this quiz to find out how much you know about dietary guidelines.
Quiz: Best & Worst Foods for Belly Fat
Do you know which foods are best and worst for belly fat? Test your knowledge with this quiz, and learn how to eat for a slimmer waistline.