Someone actually said this to me as I attempted to describe what it was like to live with an eating disorder. "It sounds like it's just a feeling," he said. Of course he was unable to understand what I was saying, even though he asked, and was curious, and was genuinely trying to understand. It is difficult to understand anyone fully and completely, and I found myself struggling to describe what exactly an eating disorder feels like.
"The best way I can explain it," I said, "is that the world shrinks so much that all I can think about is my body and hating it, or food and avoiding it. I can't control it either, it just happens. It's paralyzing."
"Does it get worse when you're alone?" he asked.
Sometimes, yes but usually no. Yes now, because I'm isolated without wanting to be. Normally, isolation is self-imposed and calming. It's a choice, and choice grants us the illusion of control. Being alone now isn't unique to me though: we're all living in an isolated, worldwide pandemic. Anxieties are high which means sometimes I worry too much about things I cannot control which means my brain focuses on the one thing I have been historically able to control which happens to be my body, and which happens to also be a lie. As one of my therapists likes to say, our bodies are smarter than we give them credit for.
There is a lot to uncover here, myths and half-truths about diet, about controlling our bodies, about food-neutrality and equally important, body neutrality, about diet culture, and health, and who to listen to regarding health, and a billion other things. But today, I'm going to focus on the "just a feeling," bit, because I've run into this statement more than a few times, and the perpetuation of myths about mental health are not only ubiquitous, but difficult to break.
What ARE Eating Disorders?
Eating disorders are illnesses that cause serious disturbances to one's diet. These include anorexia, characterized by extreme food restriction and emaciation, and bulimia, marked by purging, fasting or excessive exercise. At the opposite end of the spectrum is binge-eating disorder, in which people experience insatiable cravings that cause them to eat large amounts of food beyond what most consider "overeating." Still other eating disorders fall into a catchall category known as "eating disorders not otherwise specified." The underlying similarity between all of these disorders is a dangerous (often deadly) maladaptive approach to the body and to food.
How Heritable Are They?
According to a twin study from the National Institutes of Health, eating disorder symptoms are "moderately heritable." Twin studies differentiate environmental effects from genetic effects by comparing similarities between identical and fraternal twins. Twin studies of binge eating, self-induced vomiting, and dietary restraint suggest that these behaviors are 46-72 percent heritable. Pathological attitudes, such as body dissatisfaction, eating and weight concerns, and weight preoccupation, are 32-72 percent heritable. These finding suggest that genetics play a significant role in eating disorders, alongside environmental and societal factors.
Anorexia and bulimia often arise during the teen or early adult years, and are more common among women than men. According to a study by James Hudson, MD, ScD, and colleagues, 0.9 percent of women and 0.3 percent of U.S. men develop anorexia during their lifetime, while 1.5 percent of women and 0.5 percent of men develop bulimia. Most studies investigating eating disorders are done on women, simply because there are more women available to study.
Left untreated, eating disorders can cause serious physical problems. Bulimia can lead to gastrointestinal problems, electrolyte imbalance, and cardiovascular disease. Anorexia can cause muscle wasting, heart and brain damage, and multi-organ failure. Anorexia has been reported to have one of the highest mortality rates of any psychiatric disorder.
Nancy Zucker, PhD, a professor of psychology and neuroscience at Duke University, says that although anorexia and bulimia both have distinct features, the disorders appear to share some biological underpinnings. Both are highly heritable, but while one family member might develop anorexia, another will experience bulimia. It's also very common for someone with one type of eating disorders to later develop another.
People with eating disorders also tend to have relatively similar temperaments that are often displayed at a very young age, including: anxiousness, obsessiveness, perfectionism, and a high drive for achievement. But eating disorders are not merely a perfectionist temperament gone awry. Many perfectionists don't suffer from eating disorders. What is more likely a commonality among eating disorder patients is a faulty reward-processing system, ie, haywire brain functions.
The Eating Disordered Brain
The brains of people with anorexia have a difficult time coding reward, and are oversensitive to punishment. What this means in real time is that the reward bits of our brains are less active than the punishment bits. In THIS study, researchers scanned the brains of healthy women and women with anorexia as they played a monetary betting game. In the brains of those with anorexia, the reward processing circuits were less active when they won, and more active when they lost. They felt less joy for winning and more pain for losing.
Dopamine, the neurotransmitter responsible for emotional responses is altered in those with both anorexia and bulimia, but in opposite ways. Those with bulimia have a weaker-than-normal response in brain regions that are part of the dopamine-reward circuitry, while the same dopamine circuits in those with anorexia are overly sensitive to food-related stimuli. This makes mealtime very anxiety-producing for those with anorexia, and there is a biological reason for this reaction: the release of dopamine in the dorsal striatum erroneously triggers anxiety rather than pleasure. Other ways the brain is altered include:
- Evidence suggests the orbitofrontal cortex, which helps tell us when to stop eating, is structurally and functionally different in those with eating disorders.
-Brain activity in the dorsal striatum, which is linked to habitual behavior, is higher in those with anorexia, which may explain their rigidity related to food and to other aspects of their life.
-The brain region called the right insula helps us process taste sensations and interoception, the ability to sense one's own body signals. Most people only notice their body when something is amiss, when they have a specific pain or when their stomachs rumble. But those with anorexia may have a heightened sense of their body and pick up on sensations others do not. This interference can disturb one's ability to focus on thoughts or issues outside of their own body. Interestingly, extreme food restriction could be a coping mechanism to deal with bodily hypersensitivity. In response to starvation, the body slows down, the heart rate declines, and menstruation stops. The body essentially becomes "muted," which is helpful for those with heightened interoception.
While researchers are beginning to see patterns of brain abnormalities in eating disorders, the conclusions have been inconsistent. Severe malnourishment can cause changes to the brain that often return to normal if a person begins to eat properly. Study results can vary dramatically depending on whether participants are actively restricting food, undergoing treatment, or have recovered to a normal weight. It is therefore difficult to know whether certain brain differences are the causes or consequence of an eating disorder, but there seems to be ample evidence suggesting underlying neurological traits can drastically influence eating disorders. Emphasizing the neurological underpinnings of eating disorders can help reduce stigma and help people understand eating disorders better. They are certainly not "just feelings."
P.S. For further reading, check out this article from the American Psychological Association, this article from the Association for Psychological Science, or this article from Eating Disorder Hope, a nonprofit organization dedicated to offering hope, information, and resources to individual eating disorder sufferers, their family members, and treatment providers.