You've seen people that act addicted to food. You might notice the same patterns in yourself -- obsessing about food, sneaking to the refrigerator after supper, gobbling down heaping portions, feeling ashamed for overeating while feeling no control, even in the face of diet-related health concerns. It's eerily similar to the way an alcoholic would describe her experience with booze or a smoker would describe his history with cigarettes.
Rationale
Addiction jargon is commonly used to describe disordered eating -- think of terms like compulsive overeating and binge eating. Yet classifying food addiction as an actual disease has been a point of contention in the health community.
Because overeating can be triggered by cravings that develop after repeated exposure to certain great-tasting foods, certain of aspects of over-consumption mimic addictive behavior. What's more, overeaters seem to lack or lose the sense of when it's time to stop, meaning the drive for tasty food can trump signals that would otherwise tell the brain to stop eating. In other words, the drive to eat in some individuals seems to overtake normal regulation of hunger and satiety.
Neurological Findings
In 2010, a study published in the journal "Nature Neuroscience" presented a compelling argument that compulsive overeating might be driven by neurological changes like those seen in drug addicts. The researchers demonstrated that when laboratory rats became obese, their brains decreased "feel good" responses to stimuli, similar to changes witnessed in the brains of cocaine and heroin addicts. Obese rats were also more likely to eat compulsively when compared to healthy-weight rats. Brain receptors for dopamine showed less activity in obese rats -- a phenomenon that also occurs in human drug addicts. The most compelling findings reported were that all of these symptoms happened significantly more quickly when rats had plenty of access to super tasty food -- that is, super tasty for a rat.
Theoretically, this finding was like the human equivalent of offering a person a cookie, in which the person enjoys the cookie first time he tastes it -- but over time, the cookies fail to deliver as much pleasure. Instead of simply turning the cookie down, he is driven to gulp down more cookies -- and better tasting, sweeter cookies -- to continue to feel pleasure.
Brain Structure and Function
The development of functional MRI testing allowed scientists to visualize brain activity in patients with eating disorders. For the first time, researchers were able to watch the brain think by observing blood flow and brain activity. Using this technology, researchers at Columbia University in New York compared brain activation in the anterior cortex -- a region involved in self-control -- in women with bulemia and compared results with healthy women. Women with bulemia showed lower levels of brain stimulation in the anterior cortex as they completed tasks under the researchers' watch. While this study does not indicate that disordered eating patterns like bulemia can be classified as an addiction, the findings clearly illustrate how abnormal eating behaviors and abnormal brain function are linked.
Conflicting Viewpoints
Despite several commonalities between drug addiction and disordered eating behavior, the roots of overeating and drug addiction differ. As the science behind food addiction strengthened, Dr. Terry Wilson from Rutgers University expressed concerns that treating obesity as an addiction might shift obesity prevention efforts away from alternative preventative plans. Specifically, Wilson argued that treating obesity as a disease could detract from efforts to improve the food environment in society. According to Wilson, this "toxic food environment" rather than addiction is responsible for the drastic rise in obesity in America.
References
- Journal of Psychoactive Drugs; Food Addiction and Obesity: Evidence From Bench to Bedside; Liu et. al., June 2010
- Nature Neuroscience; Dopamine D2 receptors in addiction-like reward dysfunction and compulsive eating in obese rats; Johnson et. al.; February 2010
- Archives of General Psychiatry; Deficient Activity in the Neural Systems that Mediate Self-Regulatory Control in Bulimia Nervosa Marsh et. at.; January 2009
- The Journal of the Eating Disorders Association; Eating Disorders, Obesity and Addiction; Wilson, September 2010
