Impulsive personality linked to food addiction
The same kinds of impulsive behavior that lead some people to abuse alcohol and other drugs may also be an important contributor to an unhealthy relationship with food, according to new research from the University of Georgia.
In a paper published recently in the journal Appetite, researchers found that people with impulsive personalities were more likely to report higher levels of food addiction—a compulsive pattern of eating that is similar to drug addiction—and this in turn was associated with obesity.
"The notion of food addiction is a very new one, and one that has generated a lot of interest," said James MacKillop, the study's principal investigator and associate professor of psychology in UGA's Franklin College of Arts and Sciences. "My lab generally studies alcohol, nicotine and other forms of drug addiction, but we think it's possible to think about impulsivity, food addiction and obesity using some of the same techniques."
More than one-third of U.S. adults are obese, according to the Centers for Disease Control and Prevention, putting them at greater risk for heart disease, stroke, type 2 diabetes and certain types of cancer. The estimated annual medical cost of obesity was $147 billion in 2008 U.S. dollars, and obese people pay an average of $1,429 more in medical expenses than those of normal weight.
MacKillop and doctoral students Cara Murphy and Monika Stojek hope that their research will ultimately help physicians and other experts plan treatments and interventions for obese people who have developed an addiction to food, paving the way for a healthier lifestyle.
The study used two different scales, the Yale Food Addiction Scale and the UPPS-P Impulsive Behavior Scale, to determine levels of food addiction and impulsivity among the 233 participants. Researchers then compared these results with each participant's body mass index, which is used to determine obesity.
"Our study shows that impulsive behavior was not necessarily associated with obesity, but impulsive behaviors can lead to food addiction," MacKillop said.
That is, just because someone exhibits impulsive behavior does not mean they will become obese, but an increase in certain impulsive behaviors is linked to food addiction, which appeared to be the driving force behind higher BMI in study participants.
These results are among the first forays into the study of addictive eating habits and how they contribute to obesity. Working with a grant from UGA's Obesity Initiative, MacKillop's team now plans to expand their research by analyzing the brain activity of different individuals as they make decisions about food.
The contemporary food industry has created a wide array of eating options, and foods that are high in fat, sodium, sugar and other flavorful additives and appear to produce cravings much like illicit drugs, MacKillop said. Now they will work to see how those intense cravings might play a role in the development of obesity.
"Modern neuroscience has helped us understand how substances like drugs and alcohol co-opt areas of the brain that evolved to release dopamine and create a sense of happiness or satisfaction," he said. "And now we realize that certain types of food also hijack these brain circuits and lay the foundation for compulsive eating habits that are similar to drug addiction."