Jon Smith is a serial dieter. About 2 months after giving up on the Sugar Busters Diet and gaining 15 pounds, he decides to give it another go with the Paleo Diet. On Sunday night, with his last hurrah of pizza and Ben and Jerry’s weighing heavily in his gut, he prepares a kale smoothie for breakfast Monday morning, and packs up a large cooler of food for work. He wakes up with the best of intentions and it’s smooth sailing until 11:30am.
Then, an announcement: pizza and cupcakes in the employee lounge to celebrate the birthday of Iris Branson, from accounts receivable. Mr. Smith goes in with every intention of avoiding those calorie-laden, processed (and favorite!) foods.
He smells the pizza and his mouth literally starts to water. The rational side of his brain is fighting to avoid eating it, but deep down he knows there is no avoiding it. It is as if he has no control, so he tells himself he will have one piece, then get right back on his diet. Once the cheese hits his taste buds, he essentially goes on autopilot and doesn’t stop with the one slice of pizza. It doesn’t stop with the second, or the third. Nor with the cupcake.
He continues to gorge well past the point of feeling uncomfortable, and stops late that night only because he feels too sick to get out of his bed and go to the kitchen. All the while, he knows he shouldn’t be doing it, but he feels powerless to stop it.
Have you ever found yourself in this kind of situation?
What Is Binge Eating?
Binge Eating Disorder1 is the most common eating disorder in the United States, and involves eating large quantities of food in a short period of time accompanied by a feeling of loss of control. Data suggests binge eating is more common amongst athletes and “dieters,” as calorie restriction is a prime trigger for binges. Up until recently, binge eating was seen as a mere lack of willpower. However, as scientists better understand the brain and behavior, it is becoming clear there is a biologic basis for binge eating, and will power may have little to do with it.
Why You Can’t Stop Overeating
Binge eating is associated with dopamine release in the brain. Dopamine is a chemical that plays a role in reward circuits. For example, when a person is exposed to a pleasurable sensation, dopamine is released, and it makes the person “feel good.” Drugs like cocaine and amphetamines cause large releases of brain dopamine. When the brain of a binge eater is compared to the brain of a non-binge eater, the binge eater will release more dopamine in response to food (or even the smell of food) than the non-binge eater.2 In essence, food functions as a drug in the brain of a binge eater.
There is another class of chemicals, which are released in response to the consumption of fatty, sugary foods- endorphins. Endorphin release in the brain is associated with a pleasurable experience. Heroin and narcotic pain medications simulate endorphin release. Thus, food acts like a drug in this context as well.
Why Doesn’t Everyone Binge Eat?
The food as a drug hypothesis raises the natural question: why doesn’t everyone overeat? There is, in fact, no clear answer. It seems that obese individuals have fewer dopamine receptors in their brains. As a result, they must eat more food to feel the effects of dopamine release. Additionally, as a person over eats or binge eats in the long-term, there are permanent changes in brain chemistry, and that person will need to eating continually more food to feel the same “high,” the same way a drug addict needs to take more drug over time to feel the same effect. As behaviors continue, they become habits, and each time the behavior occurs, it becomes that much harder to break.
Binge eating is a complex disorder influenced by genetics, society, biochemistry and psychology. Effective treatment of overeating should address all aspects, and certainly involves more than just “not eating.”
- For purposes of this discussion, I will use the term binge eater to describe someone who overeats despite attempts to resist (i.e. feels a loss of control) even if he or she technically doesn’t fit the medical diagnostic criteria for Binge Eating Disorder. DSM criteria for Binge Eating Disorder can be found here: http://www.dsm5.org/Documents/Eating%20Disorders%20Fact%20Sheet.pdf ↩
- http://www.ncbi.nlm.nih.gov/pubmed/23016694 ↩