An “obesogenic” environment, behavioral influences, and genetics all play a role.
Commonly, obesity is believed to be mind over matter. The mind being your decision to eat too much, the matter being the food itself.
In an influential and comprehensive report, the Institute of Medicine challenges the notion that obesity is a lack of willpower on your part.
Instead, the report argued that Americans live in an “obesogenic” environment, or one that encourages or supports obesity.
“People have heard the advice to eat less and move more for years, and during that time a large number of Americans have become obese,” committee member Shiriki Kumanyika of the University of Pennsylvania told Reuters.
“That advice will never be out of date. But when you see the increase in obesity you ask, what changed? And the answer is, the environment. The average person cannot maintain a healthy weight in this obesity-promoting environment,” Kumanyika adds.
The historical viewpoint that blames obesity on a failure of responsibility and willpower “has been used as the basis for resisting government efforts – legislative and regulatory – to address the problem,” the report says. But the report also argued that people can’t exercise personal choice because their options are limited and “biased toward the unhealthy end of the continuum.”
That so-called continuum includes a spectrum from sugar-sweetened beverages, artificial sweeteners, and farm policies to a lack of sidewalks, a shortage of anti-obesity programs at schools, too little physical education, and narrow availability of healthy foods and drinks.
At the same time, there are physiological factors at play in obesity that make it more complicated for you to lose weight and keep it off.
“When I try to lose weight, my body will do everything it possibly can to resist losing weight,” says Arya Sharma, MD, PhD, the chair in obesity research at the University of Alberta, Canada.
“My appetite will increase, my metabolic rate will slow down, my body temperature will decrease,” he says. “My thyroid function will decrease, my sense of taste and smell will increase, as will my risk-taking behavior and my susceptibility to stress.”
Such changes, referred to as the “starvation response,” will work to “sabotage” the efforts of 95 percent of people who set out to lose weight, Sharma says. “These mechanisms will eventually win out – even years after (you start on your) diet.”
“Every person I know who has ever lost a considerable amount of weight and is keeping it off describes this as a daily on-going struggle,” he adds. “They are well aware that even the slightest interruption to their routine – an illness, an injury, a new medication, even just relationship issues or financial stressors – and boom, their weight is back, whether they like it or not.”
Some scientists disagree with Sharma’s popular view that obesity, viewed through that lens, is a chronic disease, arguing such a view creates a disincentive to lose weight.
But Sharma says “there are simply so many different causes of weight gain (from genetics, to mental health, to sleep deprivation, to stress, to eating norms and culture, adverse childhood experiences, to medications – even perhaps the bugs that happen to live in your gut…).”
Another reason obesity is so common lies in genetics, according to the Stanford University Understanding Genetics Project at the Tech Museum of Innovation (TMI).
“Lots of people are predisposed to becoming obese. This is because of their genes, “a TMI report said. “Despite an almost constant badgering from friends, family, doctors and the media, the rates for obesity continue to climb. These people are not weak or lazy; they need help in maintaining their correct weight given the new environment humans find themselves in.”
“If we can find the people who need the most help, we might be able to intervene early. Maybe something like special training in diet and exercise could help people who are more likely to be obese.”
Scientists might even find a DNA difference associated with a particular gene. If a gene involved in obesity is found, drugs could be formulated to reverse the gene’s effects.
All these factors make fat shaming particularly cruel. Given the behavioral environment, which the IOM says leans toward influencing obesity, plus many other factors including genetics, you have nothing to be ashamed about.
This doesn’t mean that obesity is destiny. But having obesity genes makes it harder to maintain the right weight. There will be people who have the genes but aren't obese and those who are. In any case, it’s more complicated than simply lacking the willpower to lose weight or just being a glutton.
February 16, 2016
Christopher Nystuen, MD, MBA