Biological factors of binge eating disorder
Around 8% of all American adults will struggle with binge eating disorder at some point in their lifetime. (1) While BED was once thought to primarily be the result of sociocultural issues, scientists are increasingly finding a number of biological factors underpinning the condition.
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Response to “palatable” food
Binge eating disorder is characterized by the consumption of an abnormally large amount of food—which can be rich in fat, salt, or sugar—and the sense of losing control over how much a person is eating. There’s a reason why the food involved in the disorder are often considered those that our society dictates “should” be eaten “in moderation.”
Eating anything will activate different receptors in the brain involved in the body’s reward center. Evolutionarily developed to ensure humans sought enough food to sustain themselves, these reward centers send “feel-good” chemicals, like dopamine and opioids, through the body. These receptors are especially active when responding to “palatable foods,” which can be those high in salt and certain sugars and fats. (2)
Normally, these rewarding chemicals have a counterpoint – a compound called acetylcholine, which helps stimulate the sense of satiation. But during episodes of binge eating, the body can become so overwhelmed by the rush of dopamine and opioids that the compound simply can’t compete. (2) This reaction is what can trigger a binge, allowing the person to continue eating without feeling physically full for longer-than-normal periods of time.
Some findings have also hinted at an inherent difference in the reward center pathways in people with BED which would make them more sensitive to dopamine—and more susceptible to disordered eating—though further research on this concept is still needed. (3)
But it’s important to remember to avoid assigning value or quantities to foods. Referring to foods as “good” or “bad” and “healthy” or “unhealthy,” recommending you “should” or “shouldn’t” eat something because of its perceived nutritional value or lack of value and recommending specific foods to eat “in moderation” or quantities to eat as “enough” or “too much” can lead to disordered eating patterns and full-blown eating disorders. (4)
Most people will experience similar episodes a few times over the course of their life, such as sitting down to a Thanksgiving dinner or a wedding reception feast and not being able to eat in moderation. It is perfectly normal to overeat at times, especially for special occasions and in social situations.
But the situation is a recurring issue for people who struggle with binge eating disorder, with episodes often happening two or more times per week. (3) And part of the reason the behavior gets repeated so frequently for some people has to do with actual physical changes within the body.
Repeated episodes of binge eating have actually been shown to change the structure of the brain and the way its reward system operates. (2) The expression of several genes involved with the release and reception of dopamine were found to be triggered by excessive binging on high-sucrose foods. (2) High-fat foods have also been connected to changes in the way the body releases and receives opioids. (2)
But while binge eating disorder causes changes in the brain, what causes binge eating to begin with may have more to do with a person’s environment.
Environmental factors of binge eating disorder
What causes binge eating disorder is a complex combination of outer- and inner- stimuli. But environmental factors frequently set these biological mechanisms off, at least initially.
There are a number of comorbid—or, concurrent—medical conditions that can occur with binge eating disorder, including anxiety and depression. The way people react to stress might be the most impactful.
Many people with BED have been found to have an increased level of stress at the onset of binging episodes. (3) How sensitive people are to stress is also considered a big predictor of binge eating behavior. more highly-sensitive people tend to be more susceptible to developing binge eating disorder. (3)
Eating any type or amount of food will trigger the parasympathetic nervous system, which diverts energy from other areas of the body to focus on digestion. The switch is almost like shifting into a lower gear and can have a soothing or sleepy effect on people, which may be used as a subconscious defense against stress. (3)
And, once again, the types of foods a person tends to binge come into play.
Studies have found that “palatable” foods often both trigger binging episodes and alleviate both the psychological and physiological effects of stress. (3) The two outcomes stem from the same mechanism of lighting up “feel good” neurochemical pathways.
Still, in many cases of binge eating disorder, people will binge eat even when they’re not hungry, especially when reacting to stress. In these cases, what they’re craving isn’t the nutrients or even the sugar and fat content of the food, but the neurological response it triggers. (3) These types of cravings can then become a conditioned response, further perpetuating binge eating behavior.
The connection between stress relief and this behavior is powerful, acting as the catalyst for changing neurochemical pathways, reinforcing changes that have already been made, or both.
Another common trigger for binge eating episodes is the societal pressure to be thin.
While eating disorders may be tied to thinness in the minds of many people, in reality, less than 6% of people struggling with an eating disorder are considered medically “underweight.” (5) In fact, having a larger body size is considered a risk factor for developing BED. (6)
Still, many people succumb to the pressure to fit societal ideals, experimenting with crash diets, fasting or other forms of extreme food deprivation to achieve their desired result.
But it’s exactly this type of restriction that can lead to episodes of binge eating. (3,6)
The pattern is sometimes called the restriction/refeeding cycle, and it’s been found at the heart of many binge eating disorder causes.
Severe food restriction has been found in some studies to lead animals toward the exact kind of high-sugar, high-fat “palatable” foods that often trigger binge eating cycles. (3) It’s also been linked to animals experiencing binge eating while in a “sated,” or non-hungry, state, which can reinforce the conditional cravings that help perpetuate BED. (3)
Extreme food restriction also leads to irritability and other negative thoughts, which have been found in other studies to be a core factor in binge eating episodes. (6)
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Treatment of binge eating disorder
Binge eating disorder is a pervasive and complex issue. But it can be treated effectively. Many people are able to overcome their binge eating behaviors through the proper therapeutic care.
What causes binge eating disorder in an individual is a huge part of determining the type of treatment the person should receive. But there are a number of different types of therapies suited to address different issues that may be at the core of BED.
Some of the most commonly prescribed treatments include:
- Cognitive behavioral therapy
- Cognitive emotional behavioral therapy
- Interpersonal psychotherapy
- Dialectical behavior therapy
- Internal family systems therapy
- Emotionally focused therapy
- Art therapy
- Movement therapy
Of these, cognitive behavioral therapy (CBT) and cognitive emotional behavior therapy (CEBT) are typically the most widely-recommended treatments for BED, because more research has been conducted on these therapies. Both types of treatment have a solid track record of helping people overcome their binge eating behaviors, through a regimen that focuses on:
- Stabilizing body weight and eating patterns
- Identifying the underlying emotions driving the disorder
- Learning to recognize those emotions when they occur
- Learning and practicing newer and healthier coping mechanisms
But many other treatments can also be effective. If more traditional forms of therapy fail to help, a number of pharmacological options may also be available for someone struggling with BED. However, a doctor should always be consulted before pursuing this route.
Regardless, it’s important to remember that help is available—and recovery is possible.
If you or someone you know is struggling with binge eating disorder, seek help immediately. Within Health is here to support you through eating disorder treatment and recovery. We offer virtual care programs for anyone with an eating disorder, and tailor treatment to your specific needs. Contact our team today to learn more about healing options.