The causes of the obesity epidemic — a plague afflicting 150 million Americans, plus the remaining 150 million who help shoulder $150 billion in annual medical costs and must suffer colleagues and loved ones succumbing to disability and early death — can be crystalized in one telling statistic: Around one in two hardware stores sells food. They mostly offer candy bars and other treacherous snacks near the checkout line. Thanks to an aggressive food industry, you cannot go anywhere without the temptation to make bad dietary decisions.

Besides keeping us alive, food is a nexus of many deep concerns — philosophical, spiritual, political, sensual. We have strong feelings about what we eat, how we eat it and how much we eat, and our feelings about what others put in their bodies are nearly as fierce. Thus obesity is seen as a moral failure: a sign of weak will, flawed character or simplemindedness.

In “A Big Fat Crisis,” Deborah A. Cohen, a medical doctor and senior scientist at the RAND Corp., removes the blame for obesity from those with the extra pounds and places it squarely on their surroundings. Her thesis is clear: Just as infectious disease and cancer result from exposure to a pathogenic and carcinogenic environment, “obesity is primarily the result of exposure to an obesogenic environment.” She makes a convincing diagnosis. But her proposed medicine — expansive government regulation — may not go down easily.

The first section of the book describes a litany of cognitive vulnerabilities. I’d call them human frailties, but many are with us for a reason. Our behavior is mostly, if not completely automatic, depending on your view of free will, and that includes eating. We’re susceptible to subtle behavioral triggers, including advertisements telling us to indulge. And because of an evolutionary landscape in which food was scarce, we stuff our bellies whenever we get the chance, which is now always. Calorie-counting and portion-size control were not big things on the savannah, so our brains don’t devote much attention to these skills. In one study, subjects underestimated their daily intake by several hundred calories. You can’t exert willpower over what you don’t notice.

While weight is correlated with self-control, those who blame too much of the former solely on too little of the latter must contend with the fact that, on average, Americans weigh 20 pounds more today than we did 30 years ago. Were we all much better people back then? Unlikely. A study of 122,000 registered nurses — people with advanced health-care training and the wherewithal to hold down difficult jobs — found that in 30 years their obesity rates tripled. Cohen writes, in reference to the proportion of Americans who are now overweight, “I don’t think it is appropriate to think of two-thirds of the population as irresponsible.”

“A Big Fat Crisis: The Hidden Forces Behind the Obesity Epidemic — and How We Can End It” by Deborah Cohen.

What has changed in recent decades, Cohen explains in the second section of her book, is the environment in which we make our food choices. She highlights three big fattening factors. The first is the reduced price of food, especially unhealthy food, because of advances in agriculture and food processing. The second is the increased availability of food — again, especially junky stuff. You can find it at 41 percent of retail stores, including furniture outlets, auto repair shops, pharmacies and the lingerie section of Macy’s. Candy, chips and soda make great impulse buys. Adding to the temptation, the number of restaurants has tripled in the past 40 years, with their serving sizes vying to keep pace. Third, food advertising has become more intrusive. The industry spends $10 billion a year on ads, with about $2 billion aimed at kids, who see dozens of TV ads for food a day. Grocery stores now earn less profit from customers than they do from companies paying for prime display spots.

Sections one and two explore a lot of ground covered elsewhere, but the third section, filling half of the book, is its raison d’être. Cohen’s arguments will upset many people, particularly those who derided Mayor Michael Bloomberg’s plan to limit New York City soda sizes as part of his “nanny state.”

Cohen’s first policy recommendation is the standardization of portion sizes. With alcohol, whether you order a beer, a glass of wine or a shot, you know that a drink is a drink. She thinks restaurants should serve food in single-portion units. Second, the government should limit “impulse marketing” by banning food from stores that aren’t dedicated to food, restricting combo meals at restaurants and keeping drive-thru windows closed outside meal times. Third, she wants to run counter-advertising that makes the downsides of fattening food more salient, the way one ad depicts body fat being poured from a soda bottle. We no longer protest regulations for building construction, consumer goods, environmental contamination, liquor sales or food safety, and yet diet-related chronic disease is a much bigger problem than food-borne illness.

Cohen compares the current situation to that of London in the 1800s, when people tossed filth out the window and left rotting carcasses in the streets, leading to widespread disease. England finally enforced sanitation standards, which required reengineering centuries-old towns to build sewers. One citizen wrote to the Times of London, “We prefer to take our chance with cholera and the rest than be bullied into health.” Sound familiar? According to Cohen, the sanitation revolution “heralded the onset of changes of such an enormous magnitude that it dwarfs everything proposed herein.”

This is not a diet book. In fact, it’s an anti-diet book, as Cohen says diets don’t work for most people. Instead, it’s a rallying cry for drastic change in how we view and manage the obesity epidemic, a voice that libertarians, industrialists and those who enjoy one-stop shopping for spackle and Snickers will not want to hear. In place of pointless finger-wagging at individuals, Cohen methodically applies principles of public health to the problem. “People are suffering,” she writes, “and thus need protection.”

Matthew Hutson is a science writer and the author of “The 7 Laws of Magical Thinking,” about the psychology of superstitition and religion.


The Hidden Forces Behind the Obesity Epidemic — and How We Can End It

By Deborah A. Cohen

Nation. 262 pp. $26.99