06/26/2014 05:51 pm ET Updated Aug 26, 2014

The Obesity Epidemic Lumbers on as We Fight Symptoms Rather Than Causes

Almost halfway through its fourth decade, the obesity epidemic is holding strong, if not gaining momentum. More than one-third of the U.S. adult population is obese and two-thirds are overweight. The personal and social costs are enormous, second only to tobacco use as a cause of mortality. The annual costs of obesity in the U.S. has been estimated to exceed $1 trillion.

How, as a society, have we responded? A New York mayor bans large soda drinks. School officials attempt to remove fatty and sugary foods from cafeterias. Fast food eateries are forced to list calorie counts of menu items. The First Lady implores the young to get more exercise and eat healthily. And from politicians to folks on the street, blame is heaped on the fast food industry and the victims themselves. These strategies have not delivered results, nor should they be expected to do so. They merely address symptoms rather than causes.

What are the causes that get no notice? They are fundamentally economic and a hint as to their character comes from taking note of who most suffers weight problems. It's our society's least privileged, the poor, the unemployed, the least educated. And among these, it's the minorities who suffer discrimination. And among these minorities, it's the women who suffer sexism as well. What accompanies this social gradient is that insecurity, stress, and a sense of powerlessness are greater the lower one's social status.

When stressed, humans, like other animals, secrete more of the hormone cortisol, which increases glucose in the bloodstream, providing energy to better deal with what is causing the stress. But that stress eventually dissipates when what generated it ends, permitting cortisol to fall back into the normal range. However, when stress is unrelenting, as it is for so many people in contemporary society, cortisol levels remain elevated and induce a craving for energy-dense foods, such as those with high sugar or high fat content, which represented a survival advantage for those living in a world of food scarcity. But in today's world, where energy-dense foods are readily available and inexpensive, the consequence is excess consumption and an overweight population. Although energy-dense junk food nourishes the problem, it is not the root cause. The omnipresence of these foods is, as economists would put it, demand driven. And on the calorie expenditure side, elevated cortisol appears to correlate with reduced physical activity. Thus the couch, an oversized bag of chips, and a soda.

The past 3.5 decades have witnessed a substantial increase in insecurity and stress around the world. This has been especially so in countries such as the U.S. and U.K., where social safety nets have been shredded as free market ideology has become increasingly dominant. Freer international trade, more rapid technological change, deregulation, and the quashing of unions have made jobs and incomes far less secure. Dramatically greater inequality has reduced relative social status for all but the most privileged. Soaring health care costs pinch family budgets. Higher college costs and a dramatic decline in government support for public universities have meant that most young people can acquire college educations only by become deeply indebted. They graduate with an average of $29,400 in student debt. More adult children, 36 percent of millenials, live in their parents' homes. Employer-provided retirement plans, where they still exist, have become less guaranteed and less generous, while the ever-present political chatter about trimming back Social Security generates insecurity as to whether even basic retirement security will survive. Social capital and neighborhood cohesion have weakened. People are ever-more time-stressed and concerned about their futures.

All of these trends have especially impacted the less well-off, and so it is to be expected that they would suffer the greatest incidence of stress and obesity. Even when they are employed, they tend to do monotonous work and have little control over how they work. Those with little control over the work process and who work under stressful conditions suffer about 50 percent higher incidence of obesity.

Financial insecurity has been increasing as has stress. The Index of Social Health of the United States, which provides a composite measure of social health or well-being, shows that based on a scale of 100, a decline from 60.0 in 1970 to 50.2 in 2011, a striking drop of 21.6 percent, even as per capita income (in 2011 dollars) increased from $16,765 to $28,130.

The overweight, and especially the obese, are stigmatized. They are blamed for eating too much, eating unhealthy foods, and getting too little exercise. They are depicted as gluttonous and slothful, which stresses them further. These victims are caught up in a feedback loop: Socially-induced stress prompts them to overeat, leading to excess weight for which they're found guilty of inadequate self-control, causing them yet further stress that releases cortisol that instructs them to eat yet more calorie-rich foods.

Although those furthest down the social ladder suffer the highest incidence of obesity, even the rich succumb to this social disease, albeit in far lesser proportions. If our economy's increasingly robust creative destruction is producing not only ever more output, but also generating greater insecurity and psychological stress, then the consequent obesity epidemic is symptomatic of a social mistake: the pursuit of maximum efficiency and economic growth even in those societies where the fundamental problem of material security has already been solved. Alongside ecological destruction, obesity may be one of the canaries dying in the mine. Both urgently invite us to rethink our social trajectory.

Co-author of "Creative Destruction, Economic Insecurity, Stress, and Epidemic Obesity," American Journal of Economics and Sociology, July 2010