Compulsive Overeating and How to Stop It

Sep 04, 2009

Per Web MD

A former FDA commissioner explains why people overeat -- and how to end poor eating habits.

By Elizabeth Lee
WebMD Feature
Reviewed by Brunilda Nazario, MD  


Does the ice cream in the freezer keep calling your name? Can't resist a jumbo bucket of popcorn at the movies?

Powerful forces you don't recognize may be driving you to overeat, according to a new book by former FDA Commissioner David Kessler, MD. The culprits: fat, salt, sugar, and brain chemistry.

Kessler stops short of calling Americans' love for sugary, fatty foods a " food addiction." But he believes there are similarities between why some people abuse drugs and why some of us can't resist every last deep-fried chip on a heaped plate of cheese-smothered nachos.

Knowing what's driving our overeating behavior is the first step to changing it, he says.

"For some, it's alcohol," Kessler tells WebMD. "For some, it's drugs. For some, it's gambling. For many of us, it's food."

Kessler, a Harvard-trained pediatrician and medical school professor at the University of California, San Francisco, started researching what would become The End of Overeating after watching an overweight woman talk about obsessive eating habits on The Oprah Winfrey Show. It sounded familiar. Kessler's own weight has zoomed up and down over the years, leaving him with suits of every size.

"For much of my life, sugar, fat, and salt held remarkable sway over my behavior," he writes.

And so the man who tackled tobacco companies while leading the FDA started researching why he couldn't turn down a chocolate chip cookie. He pored over studies on taste preferences, eating habits, and brain activity, conducted studies, and talked to food industry insiders, scientists, and people who struggled with overeating.

His theory: "Hyperpalatable" foods -- those loaded with fat, sugar, and salt -- stimulate the senses and provide a reward that leads many people to eat more to repeat the experience.

"I think the evidence is emerging, and the body of evidence is pretty significant," Kessler says.

He calls it conditioned hypereating, and here's how he says it works. When someone consumes a sugary, fatty food they enjoy, it stimulates endorphins, chemicals in the brain that signal a pleasurable experience. Those chemicals stimulate us to eat more of that type of food -- and also calm us down and make us feel good.

The brain also releases dopamine, which motivates us to pursue more of that food. And cues steer us back to it, too: the sight of the food, a road lined with familiar restaurants, perhaps a vending machine that sells a favorite candy bar. The food becomes a habit. We don't realize why we're eating it and why we can't control our appetite for it.

Once the food becomes a habit, it may not offer the same satisfaction. We look for foods higher in fat and sugar to bring back the thrill.

Kessler points to these factors as the cause of a dramatic spike in the number of overweight Americans in the past three decades.

Alternate Views on Overeating

Adam Drewnowski, director of the Center for Public Health and Nutrition at the University of Washington, isn't convinced.

"Yes, we like it, yes, we eat it, maybe our brains light up in response to it," Drewnowski says. "Are we addicted? No. Do we have to make it the mainstay of our diet? No."

Drewnowski, who is studying connections between poverty and obesity, contends other factors are making Americans fatter. His most recent study, published in the May issue of the Journal of the American Dietetic Association, examined the eating habits of 164 adults in Seattle. People with higher education and incomes were most likely to eat a lower-calorie, more nutritious diet, and to buy more costly food, according to the study.

"People who are obese are the ones who have no money, no education, eat cheap sugar and fat, and live in neighborhoods where cheap sugar and fat are the only things available," Drewnowski says. "We say they should choose better. But in our society, they have no choice."

Kessler allows that his theory of how biology drives overeating doesn't apply to everyone. He estimates that 70 million Americans are susceptible. Others, he says, don't respond to food stimuli in the same way, something that scientists haven't been able to explain.

Nora Volkow, director of the National Institute on Drug Abuse at the National Institutes of Health, sees similarities between situations that trigger drug abusers and those that make some people automatically order popcorn when they see a movie.

"It's the same biological mechanism," says Volkow, who studies dopamine connections to drug abuse and obesity.

The institute is studying brain chemistry to develop strategies to help people control those urges to overeat.

"People need to learn to handle their eating behaviors better," Volkow says. "Be aware of your conditioned responses. You can avoid that activity."

Taking Control of Your Eating Habits

Kessler believes conditioned hypereaters can take back control. He also calls for the food industry to take another look at how it makes and markets products that he believes manipulate eating behavior.

"It's become pretty egregious across the board," he says. "You look at most appetizers and main dishes at where America eats, and they're just layered and loaded with fat and sugar and salt. And it's not obvious."

An industry spokesman contends that Kessler's book doesn't reflect efforts to provide more nutritious food.

"He's got it backwards when it comes to the food industry's role," says Brian Kennedy, director of communications for the Grocery Manufacturers Association, a trade group for food and beverage companies. "We have heard our consumers and policy makers loud and clear, and are providing consumers with more products and healthier choices than ever before."

Kennedy points to other factors that cause people to become overweight, including lack of exercise.

The last time Kessler took on an industry, as FDA commissioner, he fought unsuccessfully to give the agency the power to regulate tobacco and was involved in efforts to secure a hefty settlement from tobacco companies to recover public health costs. With food, he wants to raise awareness of the cues that set many people into a hard-to-break cycle of overeating.

Instead of simply going on a diet, conditioned hypereaters need to change the way they approach food, he says.

Here are some of his tips:

  • Structure your eating -- knowing when and how you're going to eat. That plan helps you avoid the situations or foods that trigger overeating and establishes new eating patterns to replace destructive ones.
  • Set rules, such as not eating between meals. If you know you're not going to eat something, he says, your brain won't be as stimulated to steer you to that food.
  • Change the way you think about food. Instead of looking at a huge plate of french fries and thinking about how good it will make you feel, he advises saying that it's twice as much food as you need, and will make you feel bad. "Once you know you're being stimulated and bombarded," Kessler says, "you can take steps to protect yourself."