INTRODUCTION
This section briefly discusses the social and cultural forces that are driving up both obesity and type 2 diabetes rates to epidemic levels in the United States.

It also provides a review of the considerable psychological and social impacts on the individual living with type 2 diabetes and includes a discussion of current intervention approaches.

CULTURAL CHANGES AND THE RISE OF TYPE 2 DIABETES
Type 2 diabetes accounts for 90% to 95% of the nearly 21 million diabetes cases in the United States (1,2).

The disease is nearing epidemic proportions due, in part, to our aging population, but mostly as a result of a sharp increase in the prevalence of obesity and its associated insulin resistance (3). 

Results from the 2003 to 2004 National Health and Nutrition Examination Survey (NHANES), reported that an estimated 66% of U.S. adults are either overweight or obese, up from 45% in 1991 (4 - 6). Approximately 80% of those with type 2 diabetes are overweight or obese (7).

The three most important risk factors in the pathogenesis of this disease - sedentary lifestyle, poor dietary habits, and changes in body composition - are essentially modifiable risks, related to a set of profound social and cultural changes that have taken place recently in our society.

Nestle and Jacobson (8) and others, including the Federation of American Societies for Experimental Biology (9), Schumann (10,11), Battle and Brownell (12), Burros (13), Bar-Or et al. (14), USDA (15), WHO (16), and Tufts University Health & Nutrition Newsletter (17), have highlighted some of these social and cultural changes:

• The greater use of labor-saving devices and the automobile for transportation have reduced habitual activity levels. More than 60% of American adults are not regularly physically active. In fact, 25% of all adults are not active at all.
• Greater access to mass-produced high-calorie foods that are relatively inexpensive and heavily advertised, with recent emphasis on larger portion sizes. There has been a rapid growth of the food industry and its use of sophisticated marketing and merchandizing campaigns to stimulate food consumption, including fast foods, snacks, and drinks. For example, the McDonalds fast-food chain spends over a billion dollars a year on promotion of its products. The Centers for Disease Control analyzed data from four NHANES, which took place between the years of 1971 and 2000. Their analyses indicated that during this time, the average daily energy intake for men increased from 2450 to 2618 kcal (p < .01), and from 1542 to 1877 kcal (p < .01) for women (18). Put simply, Americans are eating more.
• The more hectic pace of modern life, longer working hours, and changes in family roles that reward convenience in terms of eating patterns,  and limited time available for recreation and outside activities.

Reversing these recent cultural trends that impact eating and exercise habits will require a multifaceted public health policy approach focusing on the prevention of weight gain as early in life as possible as a key strategy (8,14). In recent years, three highly powered clinical trials have shown that moderate dietary adjustments and exercise can help reduce the risk of developing type 2 diabetes in adults who are most at risk (19,20). By exercising moderately 30 minutes a day and losing 5% to 7% of body weight, high-risk study participants in both the Diabetes Prevention Program (DPP) and Finnish Diabetes Prevention Study, were able to reduce their odds of developing type 2 diabetes by 58% (21,22). Participants in these studies had glucose intolerance at entry and were at high risk for developing type 2 diabetes. Enhancing physical activity through a moderate exercise program, even without weight loss, has been found to decrease incidence of type 2 diabetes in at-risk populations by 44% (23). The social and cultural causes of obesity and type 2 diabetes suggest that a dramatic shift is needed from our current medical and behavioral models to a public health model involving prevention and public policy initiatives supported by medical and behavioral strategies. Indeed, current strivings for a medical cure of the multisystem defects inherent in type 2 diabetes involving the pancreas, liver, and peripheral tissues ignore the underlying social problems that are at the heart of the recent growth in obesity and type 2 diabetes rates. Garry W. Welch, Alan M. Jacobson, and Katie Weinger Behavioral and Mental Health Research, Joslin Diabetes Center, Boston, Massachusetts, U.S.A. REFERENCES