For younger children, parents need to be setting very clear limits as to what a healthy diet is and how to obtain an active lifestyle. If they don't, they're abandoning that parental responsibility to external forces that don't have their children's best interests at heart, such as food company advertising. And let's face it: how many ads do we see on TV for broccoli, zucchini and cauliflower? So parents absolutely must assume the role of teaching their children about what a healthy diet is, setting appropriate limits, and modeling healthful behavior themselves. Now, with regard to adolescents, parents still play an important role. But in this case they need to be more supportive and less supervisory, because too heavy a hand in adolescence can cause conflict that can actually make the situation worse.