Since orthorexics think they are eating in a way they believe to be healthy, they don’t question that there might be a negative impact to their health.

In their quest for healthy eating, many Americans are turning to restrictive diets – from vegan to Paleo to low-carb – that they believe are the most "pure" or beneficial. But when people decide to go beyond these and severely limit the types of foods they consume, they could be putting themselves at risk for nutritional deficiencies.

People who obsessively refine and restrict their diet to conform to their ideal of what is healthy could be suffering from orthorexia nervosa – which translates from Greek as "correct appetite."

Although not an officially recognized disorder in the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), orthorexia can be likened to clinically defined eating disorders, such as anorexia nervosa, says Charlotte Markey, a Rutgers University–Camden psychologist who teaches a course titled "The Psychology of Eating" and studies eating behaviors, body image and weight management. She is the author of "Smart People Don't Diet: How the Latest Science Can Help You Lose Weight Permanently."

Rutgers Today spoke with Markey about this condition, how to identify it and how it is best treated.

Rutgers Today: What is orthorexia?

Markey: Orthorexia is a form of maladaptive eating that can begin with good intentions: People start eliminating foods they consider "impure" or "bad" – sweets, sugars, carbohydrates – and before they know it, they are eating a highly limited diet. They think there is room for improvement and that they can always eat "healthier." They cut out sugar, then salt, then wheat, then dairy, and so on.

They become obsessed with what they should not be eating and keep whittling down the foods they will allow – which often impacts them socially since food is such a part of our social experiences. Since they think they are doing the "right" thing, they don't question that there might be a negative impact to their health.

Rutgers Today: What are the dangers of orthorexia?

Markey: What people don't realize is that many of those foods they are restricting, like carbohydrates, which are an important source of energy, really do serve a function. When diets become so restrictive, more than nutritional deficiencies can result: Orthorexics also can experience low energy and are at risk for depression. In severe cases, orthorexia eventually leads to malnourishment when critical nutrients are eliminated from the diet.

Rutgers Today: Can orthorexia be linked to other disorders clinically defined by the DSM-5?

Markey: In the past edition of the DSM, there was a category called "Eating Disorders Not Otherwise Specified." This classification would likely include people, like orthorexics, who are obsessed with food and how they eat.

Anorexia nervosa can be similar psychologically to orthorexia in the respect that they are both a restrictive obsession when it comes to food – it's just that orthorexics are more concerned with the quality of food rather than quantity. Anorexics eat far fewer calories than orthorexics, who oftentimes look "normal" in terms of weight.

Rutgers Today: How can people tell if they or someone they love is orthorexic?

Markey: The nutritional effects of this extreme dieting are not often obvious, but behavioral changes can be a red flag. What differentiates orthorexics from people who, say, avoid GMOs, are vegan or consume only organic foods, is that the quest for a healthy diet takes over their lives. They spend an inordinate amount of time thinking about food or they avoid social situations so as not to be tempted to eat the foods they are restricting.

It's time to be concerned when someone's life is being negatively affected or there is evidence of the person being distraught.

Rutgers Today: How is orthorexia treated?

Markey: I advise a two-pronged approach to treatment. A registered dietitian can assess whether a person is being deprived of key nutrients and, if so, help him or her structure a diet that is more rounded. The person should also find a counselor who specializes in eating disorders. Often, when people engage in negative eating patterns there is an underlying mental health issue. Maladaptive eating behaviors can be linked with depression, addictions and even anxiety disorders such as obsessive compulsive disorder, which can be treated successfully with both medication and cognitive-behavioral therapy.

While we want people to eat healthily, we don't want any eating pattern to become such an obsession that it detracts from their psychological, and even physical, health.

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