As important as a nutritious diet is for a balanced lifestyle, researchers in Toronto say some people are at risk of taking it too far and developing an unhealthy obsession with healthy eating.

In a review published in the journal Appetite, researchers from York University’s Faculty of Health examined numerous studies on a condition called orthorexia nervosa (ON), which is described as a pathological obsession with healthy eating.

“For some people, they can become obsessed with pure or clean eating to the point where it becomes distressing and can actually impair them in certain areas of life,” the study’s senior author Jennifer Mills, an associate professor in York University’s department of psychology, told CTV News Channel.

The team looked at how certain psychosocial risk factors could make someone more vulnerable or more likely to develop ON and found those who have a history of an eating disorder, obsessive-compulsive traits, dieting, poor body image, and a drive for thinness are more likely to develop a pathological obsession with healthy eating. They also discovered that vegetarians and vegans were at higher risk.

Lacto-vegetarians, those who don’t eat meat and eggs, but still eat dairy products, and those on a strict eating schedule were at the highest risk, according to the study.

“What the paper highlights is: ‘Really, we ought to be thinking of this in terms of mental health’ and for people who really take it to the extreme, they may be struggling to manage their mental health,” Mills said.

Although eating disorders are commonly associated with young women, the researchers said they found equal rates of men and women who struggle with the symptoms of ON.

Mills said ON can lead to malnourishment and it can be difficult for people with the condition to socialize in settings that involve eating.

“For people who are vulnerable, they may latch onto (the clean eating trend) and then take it to the extreme, to the point where they’re spending a lot of time researching and a lot of time purchasing food (and) preparing food,” she said. “It makes it difficult to eat with other people, it makes it difficult to go out to eat and it can be really distressing.”

As opposed to individuals with anorexia nervosa, who restrict calories to lose or maintain a certain weight, people with ON are fixated with the quality and preparation of the food they eat. The researchers said the increasing time spent on purchasing, planning, and preparing healthy meals can eventually become an “all-consuming obsession” that interferes with other aspects of life.

The team said they conducted the review because previous research into ON is limited and the condition isn’t recognized in standard psychiatric manuals for healthcare providers.

“It was surprising to me that the overwhelming majority of the articles in this field were of neutral [to] poor quality, indicating that the results of these studies must be interpreted with caution,” Sarah McComb, a Master’s student in Mills’ lab and first author of the study, said in a news release.

“It really suggests a call for more valid measurement tools of orthorexia, so that more reliable conclusions can be drawn about the true prevalence of orthorexia in the population and which psychosocial factors really put a person at risk for developing orthorexia nervosa.”

The study’s authors said a “consistent definition” for ON will make it easier for health researchers to provide better diagnosis and treatment of the condition.