Obesity is a major health problem around the world. Millions of people are affected by obesity. They may have health problems caused by obesity or find normal activities difficult. Obesity can even lead to early death. With big portion sizes, unhealthy food choices, and fast food on every corner, obesity is a bigger problem than ever before. You hear about obesity on TV and read about it online. But many people-kids and adults-don't understand how much your weight can affect your health. What happens to your body when you're obese? How do people become obese? What is life like for the people around the world who are obese? What can you do if you're overweight or obese to change your life?