April 21, 2009
Authority On Obesity Says: Retrain Your Brain
In his new book set to hit the shelves next week, the man who first made headlines when he helped President Clinton take on the cigarette industry is tackling a new kind of addiction.
Dr. David Kessler, former chief of the Food and Drug Administration, explains that he can't walk through a part of downtown San Francisco without being overwhelmed by the irresistible craving to stop at a local shop for a chocolate-covered pretzel. Why? According to him, food hijacks his brain.
The simple fact, says Dr. Kessler, is that certain people really do have a much harder time resisting unhealthy foods.
"The food industry has figured out what works," Kessler told the Associated Press. "They know what drives people to keep on eating...It's the next great public health campaign, of changing how we view food, and the food industry has to be a part of it."
He describes some of the processed sweets sold by major manufacturers as being "layered and loaded" with a tantalizing combination of fat, salt and sugar. They are often intentionally prepared so that the consumer barely even needs to chew them. Minimal effort, maximum satisfaction "“ at least in the short-run.
This does not, however, absolve consumers of their responsibility in the fight against overeating, warns Kessler.
"I have suits in every size," writes Kessler. "But once you know what's driving your behavior, you can put steps into place" to retrain your brain and teach it to resist the enticements.
At the crux of research on overeating is the question of how the brain is affected by different stimuli. There is increasing unanimity amongst neuroscientists in recent years regarding how the combination of fat and sugar excites dopamine receptors in the brain, releasing a pleasure-response similar to that initiated by alcohol or drugs.
The question then becomes: Which specific food stimuli trigger your brain to crave a specific food again? Which fast food chain or packaged little goodies light up your brain's pleasure sensors?
"You're not even aware you've learned this," explains Dr. Nora Volkow, the head of the National Institute on Drug Abuse and a seasoned expert in research dealing with the similarities between food and drug addiction.
Dr. Volkow herself confesses to a particular weakness for chocolate. "You have to fight it and fight it," she says.
Various other factors besides psychological conditioning also play a role in food addiction. Amount of exercise, metabolism and hormones all work together in food addiction and obesity.
Representatives of the food industry point to the fact that more restaurants and grocery stores than ever have begun offering healthy alternatives to the traditional calorie-laden favorites. For example, many restaurants will let you substitute a fruit salad for French fries, or a yogurt cup for ice cream.
Dr. Kessler, now working at the University of California in San Francisco, assembled a team of his fellow scientists to start researching why certain people seem to have a much harder time choosing to eat healthy.
In the first phase of their research, the team observed that rats "“ even after just being fed "“ will exert significant effort to obtain sips of a milkshake with the right combination of sugar and fat. Additionally, they found that the more sugar was added to the drink, the more the rats were willing to eat of it. The researchers point to the many low-fat foods in supermarkets that substitute sugar for the removed fat, essentially doing nothing to help consumers reduce their calorie intake.
Kessler's team then examined research results from various studies on food habits and health. They noted that most conditioned overeaters report losing control over the amount of food they eat, as well as loss of the feeling satiety and a persistent preoccupation with food. More than 40 percent of these subjects qualified as obese compared to less than 20 percent for eaters without these symptoms.
For the last part of the project, Yale neuroscientist Dana Small allowed food addicts to smell chocolate and taste chocolate while scanning their brains in an MRI machine. Rather than becoming desensitized to the aroma over time, Dr. Small found that the hyper-eaters actually became more stimulated the longer they smelled the food. Drinking the milkshake didn't satisfy their urge either. The region of the brain that anticipates the reward appeared to stay lit up even after the subjects were allowed to indulge their cravings.
Kessler also found that people who aren't obese can still be conditioned hyper-eaters, leading to the conclusion that the urge can indeed be controlled. Dr. Volkow, for instance "“ the self-described chocolate addict "“ is also a compulsive exerciser. Physical activity can also stimulate the dopamine pathway, offering a healthy way to curb the urge to binge.
As Kessler points out, society's changed perception of smoking was one of the lead factors that led to a significant drop in cigarette sales in the U.S. When people stopped seeing smoking as glamorous and "Ëcool' and started viewing it as a potentially deadly vice, more and more people started to kick the habit.
Though society's view of food has yet to follow a similar to trend, Kessler says that people simply have to start retraining their brains. Tell yourself, "I'll hate myself if I eat that," advises Kessler. Start rewiring your own brain by replacing healthy foods and activities for the fleeting neurological reward of a chocolate bar.
Design a set of rules to help yourself deal with temptation before it's staring you in the face: "I'm going to the mall, but bypassing the food court."
Start consciously avoiding those cues that you know encourage bad eating habits. If you can't go to your favorite restaurant without ordering the large plate of chili-cheese fries, start going to a new restaurant.
"I've learned to eat things that I like but things that I can control," says Kessler.
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