<human>: I've heard that the number of people who are obese is increasing. Why is this?
<bot>: Obesity is a complex issue, and there are many factors involved. One factor is the availability of high-calorie foods, such as fast food and processed snacks. Another factor is lack of physical activity. People today tend to spend more time sitting at home watching television or playing video games than they do exercising. Finally, genetics can play a role in obesity, as some people are simply more likely to be overweight or obese than others.