I read most of the posts and lots of great ideas and thoughts.
Ill try to offer another side as well since i didnt see any of the posts hit on this.
I am in the military, Marine Corps specifically and most who know about the Marine Corps or know of others who have been in, know that we PT a pretty good amount. Ranging from cross fit workouts to running 5+ miles three times a week. We have weight and body composition standards that we must adhere to and physical fitness standards. If we do not adhere to these weight standards we get put on a weight control program.
Since we have these standards, if they are not complied with, your career can be and will be affected. In my mind you would think this would be enough to ensure Marines would remain in good physical condition. Unfortunately this is not the case as many Marines remain out of shape.
This seems to go hand in hand with the old saying, "You can lead a horse to water but you cant make him drink the water".
While i think America does need to take necessary steps to try and work on the issue of obesity and help people lead healthier lives, it also requires leg work on behalf of the person themselves. This is a lot of times, where the problem lies.
Like others have stated we live in a society where everyone is so used to comfort and lazy. Everyone wants a magic pill or potion that will do the trick. Well this obviously isnt the case. People must put in hard work and effort and they just arent accustomed to that.
So while i agree with healthcare insurance providers providing incentives and food stamps only being for healthy foods or alternatives it still falls on the individual. Noone can make someone do something they dont want to do. Even if they do want to lose weight its a hard and long road for most and this in itself will deter a lot of people regardless of incentives provided.