When author Glennon Doyle revealed her struggle with anorexia last year, she said that she was shocked by her new diagnosis, having spent years of her life believing she had bulimia. While it’s easy to wonder how on earth this misdiagnosis could have happened—anorexia and bulimia are quite different, aren’t they?—when you look at the driving behaviors of the two eating disorders, it starts to make sense. As we shared at the time, Doyle’s diagnosis highlights the fact that most, if not all, eating disorders have one shared root cause: food restriction.

While there’s a general understanding that food restriction is part of anorexia, many people—including eating disorder professionals and those suffering themselves—fail to recognize that it’s a core component of other eating disorders, like bulimia, binge eating disorder (BED), and avoidant restrictive food intake disorder (ARFID). Here’s what everyone should know about how deprivation and hyper-vigilance often fuels the fire of illnesses across the eating disorder spectrum.

How food restriction fuels eating disorders besides anorexia

Eating disorders are never the result of a single cause, but rather the manifestation of complex biological, psychological, and social factors. That said, we do know that food restriction is frequently a driving factor in most eating disorders—not just anorexia.

“It’s true that restriction is a significant component of anorexia, however, I can confidently say that it’s present in all eating disorders, either in the form of actual behavior or mentality,” Equip Dietitian Gabriela Cohen says. “Let's think about binge eating disorder. Why do we think that people feel the need to binge on food? Because they’re not allowing themselves to have it on a consistent basis, or to have the amounts or types of food they desire, which is the definition of restriction.”

Equip Dietitian Caitlyn Neuendorf agrees, explaining that all types of eating disorders can be rooted in restriction, and that “restriction” doesn’t necessarily have to mean limiting food in order to avoid weight gain; it can also be physiological or psychological. “In patients with ARFID, many are restricting food variety, volume, or both,” she explains. “In patients with BED, there is often both a physiological and psychological restriction going on concurrently.” She says that even if a person is eating throughout the day, if they’re mentally restricting—meaning they only focus on nutrients, avoid foods they think they “shouldn’t” eat, or make food rules for themselves (like just one French fry or just one bite of cake)—their brain still registers that as restriction. “This can lead to binging behaviors and an unhealthy relationship with food,” she says.

Here’s a brief look at how food restriction might show up in different eating disorder diagnoses:

• Anorexia: This is the eating disorder most of us associate with restriction, and for good reason, as restricting food is a defining characteristic of the disease. Those with anorexia severely restrict their food intake, often eliminating entire food groups and adhering to strict food rules. There are two types of anorexia: restricting subtype and binge-purge subtype. The former is defined purely by food restriction, while the latter is defined by restriction followed by episodes of binge eating and purging.
• Bulimia: Bulimia is defined by repeated episodes of binge eating and purging. Someone with bulimia feels a loss of control during binges, and shame after them. In most cases, binges are preceded by periods of restriction, and the biological hunger that results from that restriction can both trigger a binge and contribute to the out-of-control feeling. Often, people with bulimia also restrict after a binge in an effort to “make up” for it.
• BED: Just like with bulimia, those with BED engage in repeated episodes of binge eating accompanied by a loss of control, followed by feelings of shame. And again, in most cases, the binges come after a person has been restricting, for the same reasons outlined above (more on this cycle below).
• ARFID: In all the diagnoses above, restriction is related to thoughts and fears around weight gain and body size. With ARFID, this is almost never the case, but the restricting behavior is still there. People with ARFID restrict both the type and amount of food they eat, usually due to anxieties about negative consequences of eating, extreme issues with food texture/taste/smell/etc, or a lack of interest in food. The underlying reasons differ, but the restriction remains the same.

Understanding the binge-restrict cycle

It’s widely understood that both bulimia and BED are characterized by episodes of binge eating. But what’s not often talked about is that most binges are preceded by a period of restriction.

Most people with eating disorders not only assign morality to foods—labeling foods like salad as “good” and burgers as “bad,” for instance—but also tie their own self-worth to what they eat and don’t eat. This means that their days are governed by strict food rules, leading to mental exhaustion, physical hunger, and almost inevitable “slip-ups.” And when a slip-up happens, “since we know we ‘shouldn’t’ be eating that food, the now-or-never mentality kicks in, which leads to a binge, followed by the same-restriction cycle,” says Cohen. This explanation clearly shows the way in which restriction contributes to binge eating disorder. With bulimia, the cycle is nearly the same—restriction, binge, shame, restriction—except that there are usually purging behaviors after the binge.

This cycle doesn’t have anything to do with self-control or willpower; it’s a biological inevitability. After a period of food restriction, the biological drive for food is a survival tool. When you don’t eat enough, that sends signals to the brain that food is scarce, causing it to seek out large quantities of food when possible. In other words, for people with BED and bulimia, the binge eating and purging behaviors wouldn’t occur were it not for the restriction that came before them.

Food restriction is often praised—and that can be a slippery slope into an eating disorder

When Equip Email Marketing Lead Morgan Cornacchini was initially diagnosed with anorexia, she says she was met with more admiration than worry. “Society praises restriction,” Cornacchini says. “When my eating disorder started, I got more compliments than notes of concern. People applauded my ‘healthy willpower’ and my weight changes. This praise fueled my eating disorder and distracted me from the fact that I was sick.”

Cornaccini’s experience is unfortunately relatable to many who have been diagnosed with anorexia. After all, we live in a world that’s dominated by diet culture, a system of social beliefs and expectations that values thinness over everything else. While this insidious messaging affects us all, it can be particularly dangerous to those who are predisposed to develop eating disorders. Dieting—otherwise known as “inhibition of eating behavior” or restriction—also almost invariably leads to an obsession with food, and dieting is a known risk factor for developing an eating disorder.

Cornacchini adds that all people—whether they’re struggling with a diagnosed eating disorder, supporting a loved one who is struggling with one, or have simply been exposed to toxic societal messaging around food—can work to challenge their thoughts on restriction.

“We can start by noticing and changing how we talk to others and ourselves about what we’re eating and our bodies,” she says. “Are you praising others’ weight changes or even your own? Are you commenting about what others are eating? What is your internal dialogue surrounding your own food choices or body? What we say to ourselves and others can have a bigger impact than we think.”

Why people restrict—and how we address it head-on in treatment

While many people may understand how extreme restriction can manifest in one very specific eating disorder, the vast majority still aren’t aware that any form of physical or psychological food restriction can contribute to a variety of eating disorders, disordered eating, or general harm to your mental or physical health.

But despite all those negative consequences, restricting does serve a purpose for people with eating disorders—as with all disordered behaviors, as destructive as restricting may be, people turn to it for a reason. For many, restriction is a coping mechanism gone awry. Restricting might begin as a way to cope with tough emotions, helping people distract themselves from or numb out challenging feelings. Restricting can also make people feel good, not only because the act itself is praised by society, but also because it spares those with eating disorders the guilt and shame they often feel for honoring their own hunger.

Regardless of the purpose it’s serving, restriction is always one of the first things we tackle in Equip treatment. We know that a malnourished brain doesn’t think clearly or take in new information well, and so our very first priority is renourishment and normalizing eating habits (which entails stopping any restriction behaviors).

At Equip, patients and their loved ones work closely with a registered dietitian to address restriction head-on. Though our specific treatment approach is tailored to each patient’s unique needs, in practice this might look like:

• Recognizing the gap between daily nutritional requirements and current intake, and how that gap might be perpetuating disordered behaviors
• Prioritizing regular meals and snacks throughout the day (eating every three to four hours, always eating within one hour of waking up)
• Learning to advocate for oneself in settings that might lead to skipping a meal or snack (like social events or obligations at school or work)
• Diversifying the types of food a patient will eat, expanding beyond “safe” foods. This is important both for helping patients shed the rigid constraints of their eating disorder and for meeting macro- and micronutrient needs
• Identifying food rules and developing a plan to challenge or break them
• Providing the nutrition education patients need to become a savvy consumer of food- and body related media

Restriction may look simple and harmless on its surface—who would bat an eye if someone declared they were cutting out sugar for a month?—but in reality, it can become a disordered compulsion that fuels an eating disorder (and not just anorexia). The good news is that, with the right support and tools, everyone struggling can break free of the restriction cycle. And once restriction is gone, there’s room for its opposite: freedom.