“Orthorexia nervosa is an eating disorder that involves a fixation on healthy eating and ritualistic behavior,” explains Rafaat W. Girgis, M.D., a board-certified psychiatrist at Moment of Clarity, a mental health treatment center.

The term “orthorexia nervosa” was coined by physician Steven Bratman in 19971, and it translates to “right” or “correct” (ortho) and “appetite” (orexis) in Greek. In essence, orthorexia is a severe obsession with eating healthy. 

Orthorexia is more common among younger people, affecting between 6.9% and 45.5% of adolescents and young adults2. The wide range is due to discrepancies in different studies, suggesting that this eating disorder calls for more organized research to assess prevalence accurately. However, the presence of orthorexia does seem to be steadily increasing in recent years, likely for reasons we’ll touch on in a bit.

The thing is, “healthy” eating looks different for everybody. One person could see a very restrictive vegan diet as healthy; others a raw meat diet, some a low-carb diet, and so on—which makes this eating disorder difficult to identify. 

“[Orthorexia] often just looks like healthy eating. The signs of rigidity, obsessiveness about disease, and health are often unrecognized,”” adds registered dietitian and founder of Real Nutrition Amy Shapiro, R.D.

Say two people were on a road trip and had to stop for a meal at a diner. Both people may be healthy eaters in their day-to-day and prefer minimally processed natural foods. However, the person struggling with orthorexia will likely feel much more guilt and anxiety surrounding the diner food—even if it’s the only option.

That person with orthorexic tendencies may feel the urge to skip the meal altogether for the sake of preserving their clean eating patterns, while the other person may be able to consume the healthiest option they find on the menu without lasting shame or anxiety about how it will impact them. In essence, people who struggle with orthorexia never allow for imperfection when it comes to their diet, and if they have to for any reason, intense emotional discomfort follows.

This same situation can be applied to events like birthdays, holidays, and other celebrations where available food items may not be as healthy as one is used to.

This also makes the disease more difficult to treat, says Girgis, since many with orthorexia “believe they are right and refuse to see the negative in what they are doing to themselves,” he says.