If you are interested in the cultural issues that underlie the obesity epidemic, the Rudd Center at Yale’s website is required reading. They have done some great research on the social stigmatization around weight, and in my opinion have some of the most progressive and comprehensive ideas on making real change at the national level.
Here’s some info from their site on the shift in public opinion around obesity. Interesting reading!
There has been an interesting trajectory of public opinion about obesity. The majority of Americans are clearly concerned with obesity and there is growing support for obesity-targeted policies. The following table presents the changes that have been found in support of strategies that influence the environment in order to promote better nutrition.

Trends in Public Opinion 2001 2003 2004
Favor taxing foods 33% 40% 54%
Favor restricting children’s food advertising 57% 56% 73%
Favor soft drink / snack food bans in schools 47% 59% 69%
Favor required calorie labeling in restaurants 74% 80%

Source: Brownell KD. The chronicling of obesity: Growing awareness of its social, economic, and political contexts. J of Health Politics and Law. 2005; 955-64.