Evidence Piles Up for Food Addiction
The classic model of addiction centers on the prolonged misuse of substances that make long-term changes in the brain function of affected individuals. These changes make a person reliant on the substance in question and also lead to additional symptoms, such as a loss of control over the intake of that substance, recurring urges to use more of that substance and the onset of withdrawal when the brain doesn’t receive the amount of the substance it has come to expect. The American Psychiatric Association (APA) has long recognized the existence of substance addiction, as well as the existence of dysfunctional, non-addiction-related substance abuse. Since 2013, the APA has included substance abuse and substance addiction (which commonly have overlapping symptoms) under a single diagnostic heading called substance use disorder.
Some people develop many of the brain and behavioral changes classically associated with substance addiction while participating in common activities that don’t involve substance intake. In addition to food consumption, candidate activities include having sex, gambling, playing games on the Internet and going shopping. Experts in the field use the terms behavioral addiction and process addiction to describe the dysfunctional, damaging participation in such usually harmless endeavors. In May 2013, the American Psychiatric Association established an official category for the diagnosis of behavioral addiction, which the organization calls addictive disorder. However, as of 2014, the only behavioral addiction/addictive disorder with an established APA-sanctioned definition is gambling disorder.
Although there is no APA definition for food addiction, doctors and researchers have accumulated significant evidence that indicates that certain people have a dysfunctional, addictive relationship to the consumption of foods that substantially boost the amount of pleasure produced inside the brain. Specific foods capable of creating such a spike in pleasure levels include high-fat foods , foods high in carbohydrates called sugars (sodas, ice cream, etc.), foods high in carbohydrates called starches (refined breads and pasta, etc.) and foods with a high salt content (pretzels, potato chips, etc.). Researchers at Yale University have developed a tool called the Yale Food Addiction Scale to detect eating patterns that point toward an addictive relationship to the intake of these or other foods.
In the two studies published in Frontiers in Psychology, researchers from Germany’s University of Wurzburg, Luxembourg’s University of Luxembourg and Belgium’s University of Leuven conducted experiments designed to detect loss of control over the intake of certain foods, one of the key potential indicators of a food addiction. In the first study, the members of a group of hungry women were asked to rapidly identify a series of randomly presented computer images. Some of these images depicted high-fat or high-sugar foods, while others depicted items unrelated to eating. Prior to taking part in the test, all of the women underwent body weight measurements and also detailed their history of dieting. When the researchers matched this background information with the results of the image testing, they found that the women with higher body weights and problematic dieting histories had a substantially harder time stopping themselves from acting impulsively and misidentifying the non-food-related images as food-related images.
In the second study, the researchers gave the same image test to a mixed group of women, some of whom were hungry and some of whom had recently eaten. Some of the women who had recently eaten noted that they felt increased urges to eat even more after viewing the food-related images, despite their current full condition. When the researchers looked at the body weights and dieting histories of the women who made these declarations, they found that women with higher body weights and problematic dieting histories were considerably more likely to want to eat again despite being full. The study’s authors note the need for additional research that explores the connection between hunger levels, body weight, dieting history and loss of control over food-related urges.