Narrator: This is Science Today. It's not just overeating that's causing childhood obesity; it's changes in society that we often don't realize. Patricia Crawford, co-director of the center for Weight and Health at the University of California , Berkeley says the way neighborhoods are organized today only add to the problem.
Crawford: We have an environment where children sit during the day; they sit on the way to school, the way home from school, we have children at home by themselves and the parents don't want them to go out where it may not be as safe. We have other situations where parents are home and they still want to supervise their children when they're out and they don't have time.
Narrator: Crawford says marketing is another huge factor contributing to childhood obesity.
Crawford: The television shows, the video games, the computers, all of the ways in which kids can be inactive have really been promoted. And the ways in which kids could be active have actually been deemphasized in our society because it's harder for the children to take part in those.
Narrator: For Science Today, I'm Larissa Branin.