While I can’t speak for everyone who has or has had an eating disorder, I can say with certainty that my own years-long issues with food restriction started with a diet. It makes perfect sense, of course: the foundation of a diet designed for weight loss is food restriction. While it’s always important to keep in mind that eating disorders are not a matter of choice or vanity, but are complex, multi-faceted brain diseases, most eating disorders are inherently rooted in restriction.

So while there are biological, psychological, and social risk factors that can contribute to the development of an eating disorder, there is often an environmental or behavioral trigger—like being in a negative energy balance due to a restrictive diet—that “turns on” the eating disorder. Read on to better understand how diets and eating disorders intersect, and how to get help if a diet goes too far.

What the research says about dieting and eating disorders

“Dieting is one of the strongest predictors for the development of an eating disorder,” says Equip Dietitian Lead Tanya Hargrave-Klein MS, RDN. “Research reveals a stark connection between dieting and eating disorders in adolescents.”

Hargrave-Klein cites one three-year study, which found that teenage girls who dieted severely were 18 times more likely to develop an eating disorder than their non-dieting peers. “Even moderate dieting significantly increased risk, making girls five times more likely to develop a disorder,” she explains. “A more recent study found that female and male adolescents who dieted were more likely to exhibit eating disorder psychopathology and behaviors, including laxative use, compulsive exercise, and dietary restraint.”

Even when a diet is not framed as a strict or punishing route to weight loss, Hargrave-Klein says the underlying restriction inherent in almost all diets can still set in motion a cycle of disordered eating. “From my perspective as a registered dietitian specializing in eating disorders, I've observed that dieting, even when presented as ‘healthy’ eating, commonly precedes the onset of an eating disorder,” she says.

Why dieting is a risk factor for eating disorders

Research has consistently identified dieting as one of the strongest predictors and a significant risk factor for the development of an eating disorder.

In some cases, this may be due to what experts refer to as the “diet cycle,” which begins with a restrictive diet (i.e. limiting the amount or type of food eaten), and inevitably leads to physical and psychological deprivation. This then leads to breaking the diet rules through overeating or a binge, resulting in guilt and dissatisfaction with weight or shape, which leads back to another diet. In other words, diets generally lead to the binge-restrict cycle, a pattern of behavior that plays a key role in many eating disorders.

As mentioned above, diets can also be the external factor that flips “on” an eating disorder in someone who is vulnerable to developing one. “Some people have a heightened susceptibility to eating disorders, though the precise reasons remain a mystery,” Hargrave-Klein says. “The critical trigger for these disorders often appears to be an energy deficit, which isn't always a deliberate choice. In some cases, individuals may inadvertently reduce their caloric intake while attempting to eat ‘healthy.’ For athletes, intense training can lead to an unintentional underfueling that doesn't meet their energy expenditure. Alternatively, the deficit may stem from an intentional effort to lose weight through dieting.” But the important takeaway is that being in a calorie deficit can contribute to the development of an eating disorder, no matter the reason.

Is it possible to diet in a healthy way?

Many people are initially drawn to diets because they can effectively cause short-term weight loss, and in our society, weight loss tends to be universally praised as a good thing. But putting aside the fact that weighing less doesn’t make a person more valuable or worthy or healthier—studies have also consistently shown that most dieters regain the weight they lose, and that diets themselves often promote the adoption of disordered eating behaviors. So in most cases, dieting for weight loss doesn’t promote true health.

That said, Hargrave-Klein is clear that in some particular instances, specific dietary modifications are medically necessary and may be considered healthy. “Individuals with conditions like celiac disease or dairy allergies must adhere to specific diets that restrict certain foods,” Hargrave-Klein says. “These diets, while limiting, are distinct because they provide sufficient energy and do not promote weight loss or an energy deficit. In these cases, following such a diet is essential for managing the health condition and, therefore, can be considered healthy.”

However, these diets are specific to those with particular medical needs or conditions; weight loss diets and their relation to “health” are a different story. “For years, the diet and wellness industry has peddled the promise of health through weight loss,” Hargrave-Klein says. “But behind the glossy advertisements and celebrity endorsements lies a darker truth: the pursuit of a smaller size can significantly increase the risk of developing a dangerous eating disorder. This focus on weight loss often leads to an energy deficit, a precarious state that can trigger the onset of an eating disorder. It's a risk frequently omitted from weight-loss diet marketing, leaving consumers vulnerable to a devastating spiral.”

The important takeaway here is that weight loss is not synonymous with health. In fact, there are a variety of health-promoting behaviors that anyone can adopt that have nothing to do with weight. “As an anti-diet dietitian, I propose to clients a different path to well-being, one that prioritizes genuine health over the scale,” Hargrave-Klein says. “Instead of fixating on weight, individuals can cultivate health through adequate sleep, stress management, joyful movement, and strong social connections. These lifestyle choices offer profound benefits without the perilous gamble of dieting, providing a safer, more sustainable route to a healthier life.”

Diet vs. eating disorder: how to tell the difference

First, let’s define the two terms.

Diet: While the word “diet” can refer to what a person eats in general, it’s more often used to describe weight loss eating plans. In that context, a diet is typically considered an eating plan that requires a person to eat smaller quantities of food or only specific types of food in order to lose weight.

Eating disorders: Eating disorders are mental illnesses characterized by severe and continuous disturbances in behaviors when it comes to food. Eating disorders also include distressing thoughts and emotions and have serious—even potentially deadly—consequences.

“Diets and eating disorders, while sharing common traits such as calorie restriction, weight monitoring, excessive exercise, and food logging, diverge significantly in their nature and impact,” Hargrave-Klein says. “A key distinction lies in their controllability: dieting is a voluntary practice a person can choose to halt or stop at will, whereas it requires professional treatment to address an eating disorder.”

Diets and eating disorders also differ in how significantly they impact a person’s daily life. “Dieting typically has a minimal effect on one's daily routine and overall quality of life,” Hargrave-Klein says. “In contrast, an eating disorder exerts pervasive control over daily life, severely diminishing quality of life.”

And while the “rules” of a diet typically remain consistent throughout its duration, Hargrave-Klein points out just how volatile and extreme eating disorder rules can be over time. “With an eating disorder, food rules tend to morph and multiply, becoming increasingly rigid and complex,” she says. “While a diet solely involves food, an eating disorder may also encompass the misuse of laxatives or diuretics, or other purging behaviors.”

Some of the main differences between a diet and an eating disorder include:

• The duration. Diets usually last for a finite amount of time while eating disorders have no natural end.
• The significance of its impact. Unlike diets, eating disorders significantly impair the physical, emotional, professional, and/or social areas of a person’s life.
• How much psychological space it occupies. Eating disorders often involve obsessive and compulsive thoughts and behaviors associated with food, exercise, or body size and shape, whereas someone on a diet won’t think about it excessively.
• The importance. While diets are usually solely rooted in a desire to achieve a certain weight, eating disorders are typically attached to much higher stakes, rules, and emotions.
• The ability to choose. Going on a diet is usually a choice someone makes; an eating disorder is not. While a person can decide whether they want to remain on a diet or not, a person cannot simply decide to stop having an eating disorder.

What to do if you’re worried your diet is becoming disordered

If you're worried your diet (or the diet of a loved one) is veering into eating disorder territory, the most important first step is to seek professional support from an eating disorder specialist. Know that there’s no such thing as “not sick enough” to get help, and that earlier intervention is associated with better outcomes. Reach out to an eating disorder-informed therapist or dietitian, or schedule a call with an Equip team member. You can also take our free, 5-minute screener to help you assess if you or your loved one might have an eating disorder.

“Don't delay,” Hargrave-Klein says. “Schedule a consultation with a therapist or medical provider specializing in eating disorders to request an assessment.”

FAQ

Do diets cause eating disorders?

While not all diets will lead to an eating disorder, research consistently identifies dieting as the single most significant behavioral risk factor for developing an eating disorder. Because eating disorders are complex mental illnesses with underlying biological, psychological, and sociocultural roots, dieting may act as a trigger and activate these underlying vulnerabilities in a susceptible individual.

Can I go on a diet if I’m in recovery from an eating disorder?

Experts generally agree that engaging in a diet is not only incompatible with eating disorder recovery, but can be highly detrimental. Because dieting involves external rules around food restriction, judging foods as “good” or “bad,” calorie counting, meal timing, and more, those in recovery from eating disorders may experience a relapse when engaging with rules that so closely mimic the core behaviors of a disorder.

How can I tell if a loved one’s diet is actually an eating disorder?

While a diet is typically considered an eating plan that includes smaller quantities of food or only specific types of food in order to achieve a goal of becoming thinner, eating disorders are mental illnesses characterized by severe and continuous disturbances in thoughts and behaviors related to food. While a diet is a lifestyle choice, an eating disorder is not. If you’re concerned about a loved one, our free eating disorder screener can help you determine next steps.