America's growing concern about fatness during the twentieth century developed in parallel with a society that made it increasingly harder to live a healthy lifestyle. Since the 1970s, sweeping political, economic, cultural, and familial changes have occurred in the United States. Many researchers argue that these changes have created an "obesogenic" environment that has contributed to the increased prevalence of overweight and obesity in America by favoring inactivity and the over consumption of highly-processed, calorie-dense foods and beverages. As a result, the field of public health has increasingly begun to recognize obesity as a "societal disease." In 2001, The Surgeon General's Call to Action to Prevent and Decrease Overweight and Obesity categorized the number of overweight and obese Americans as reaching "nationwide epidemic proportions." Since that time, America has waged an all-out "war on obesity." Instead of a broader emphasis on health promotion, some public health researchers have suggested that this heightened focus on obesity is 1) guided by America's historically-rooted social disdain for fatness and 2) insufficient to improve the healthy lifestyles of Americans. In searching for a solution to the so-called "obesity epidemic," a growing number of researchers have begun to look to models of social change. After an introductory chapter describing the scope of the problem, this dissertation provides an historical analysis of two, relevant social change models. The first historical case study is an examination of the Centers for Disease Control and Prevention's VERB social marketing campaign. The second study explores the model of social movements through the history of the aerobics "boom" of 1970s America. Based on these histories, this dissertation concludes by proposing a blended approach that harnesses the strengths of both models to organize and advance America's healthy living movement. / text