Obesity causing lower life expectancy in today's kids

It's no secret that obesity is not only on the rise, but has become one of (if not the) biggest health concern for people of all ages in North America, Europe, Australia and various other countries/continents. The bloggers at That's Fit have covered a variety of topics relating to the subject including everything from new ambulances equipped especially to transport obese patients (Rigel Gregg) to how overweight patients have a higher likelihood of complications after surgery (Bethany Sanders).

One of the most disturbing things I've read about the increase in overweight adults and kids, is this article which reports on a Canadian study that says kids aged 2 to 17 will be the first generation ever to have a lower life expectancy than their parents because of skyrocketing obesity rates. According to the study, approximately one-quarter of Canadian kids (rates are similar in American depending on what source you check) are extremely overweight and at a higher risk of a number of conditions including Type 2 diabetes, joint problems, heart attack and stroke.

The article mentions that one way to help kids lose weight is to change the views that overeating is alright and that exercise isn't cool. It also mentions the problems associated with marketing junk food and fast food to kids. In addition, parents need to help their children make better choices when it comes to both food and exercise. What do you think is the key to lowering obesity rates among kids?