Everyone who has ever turned to their friends Ben and Jerry for solace following a break-up is aware that painful emotions often lead to overeating. Yet when discussing the obesity epidemic among low-income families, policymakers tend to focus on more tangible factors, such as the cost and availability of healthy food.
Over the past few years, a number of researchers have begun pointing out this emotion blindness, suggesting the stress of poverty is an underappreciated underlying problem. Two new studies that confirm and refine this proposition have just been published.
A study from Scotland, published in the journal Appetite, demonstrates a connection between overeating and the anxiety that stems from income inequality. American researchers, writing in Psychological Science, find a link between growing up poor and a propensity to consume calories in the absence of hunger.
A more equal society, where most members feel respected and experience a sense of belonging, is a lower-stress society, and this reduces anxiety-based eating.
"It appears that humans and animals respond similarly to harsh and scarce environments, and this response takes the form of preemptive increases in food consumption," writes a research team led by Boyka Bratanova of the University of St. Andrews and Steve Loughnan of the University of Edinburgh.
The American researchers, led by Texas Christian University psychologist Sarah Hill, provide evidence that this dynamic may be established during childhood, and stubbornly persist into adulthood.
Hill and her colleagues conducted three experiments in which they either measured or manipulated the energy needs of a group of students, and then provided snacks for them to eat. In one, 60 female undergraduates filled out a form indicating their family's socioeconomic status, both when they were children and at the current moment.
Half drank a 12-ounce can of Sprite (which satisfied their immediate energy needs), while the others drank an equivalent amount of mineral water. Ten minutes later, all we're asked to try, and evaluate, some cookies.
Those who grew up in prosperous households consumed fewer cookies if they had just consumed the sweetened drink. Those who were raised in difficult economic circumstances ate just as many, whether they drank the water or the soda.
"Among individuals who grew up in high-socioeconomic status environments, food intake varied according to immediate physiological energy need," the researchers write. "These individuals consumed more calories when their current energy need was high than when it was low."
"For individuals who grew up in low-socioeconomic status environments, however, the relationship between physiological need and food intake was decoupled. Their food intake appeared to be guided primarily by opportunity."
The Scottish study featured two experiments, also carried out on groups of undergraduates. In one, 54 participants wrote about the extent to which they identified with people living either in "material abundance" or "financial scarcity." They then were then provided with snacks (cookies and crackers) to munch on as they watched two short videos.
Strikingly, the students consumed an average of 54 percent more calories when they were primed to feel poor. They also reported liking the snacks more than their counterparts, and expressed a stronger intent to buy them in the future.
"Feeling poor relative to others had a clear effect on calorie consumption," the researchers conclude, adding that the overeating was due to "increased anxiety—particularly anxiety due to anticipated negative social evaluation."
Intriguingly, the Scottish researchers find this dynamic doesn't exclusively impact the poor. While poverty is the dominant driver of this dynamic, being wealthier than those around you can also produce unease—"a fear of being envied"—and that, too, may lead one to pack on the pounds.
So a more equal society, where most members feel respected and experience a sense of belonging, is a lower-stress society, and this reduces anxiety-based eating, which, in turn, combats obesity.
Will we see such a thing any time soon? Fat chance.
Findings is a daily column by Pacific Standard staff writer Tom Jacobs, who scours the psychological-research journals to discover new insights into human behavior, ranging from the origins of our political beliefs to the cultivation of creativity.