Q. One of my clients seems to be excessively interested in maintaining a healthy diet. Although this seemed healthy on the surface, I think she is carrying it too far. Is this a type of eating disorder or just a fad? (LY, Reno, NV)

A. You could be describing what may be a case of orthorexia nervosa (ON), an alleged eating disorder in which a person is excessively preoccupied with consuming only “healthy” foods. Persons with this condition, first described by Bratman in 1997, seem fixated on healthy foods or have a dependence on healthy foods (Bratman S, Knight D. Health food junkies: overcoming the obsession with healthful eating. New York: Broadway Books, 2000).

A healthy diet is of course, a good thing, but with ON the obsessive and compulsive characteristics become pathological and come to dominate a person’s life. A person with ON person seeks out only “pure” foods and shops that sell them, and a unhealthy lifestyle may result. Some studies have also reported that these patients develop an attitude of superiority and obsessive-phobic behavior. When an individual with ON breaks the dietary rules, she has feelings of intense anxiety, guilt and shame, followed by even more strict food restriction A few clinical studies have attempted to better define the disorder and to differentiate it from a healthy concern about one’s diet and, critically, also from a anorexia nervosa. The difference appears to be the extreme preoccupation with a healthy diet and the judgmental attitude toward others who do not follow a similar “healthy” diet.

At this point, ON is not a formal disorder, and its inclusion as a mental disorder is still debatable. A Hungarian group has employed the ORTO-15, a questionnaire about ON symptoms, with a food choice list indicating foods participants choose to consume and 10 additional orthorexia-related questions (BMC Psychiatry. 2014; 14:59). Varga et al. found that age and body mass index were significantly associated with ON. Individuals with higher scores on the ORTO-15 also reported eating more whole wheat cereals, less white wheat cereals, more fruit and vegetables, and shopping only at health food stores. These individuals also had a greater tendency to advocate their healthy diet to friends and family members. There were no significant differences between males and females. Those with higher scores on the ORTO-15 also tended to view overweight as a sign of weakness and to state that people should be blamed for their own diseases.

The authors feel that further research will identify the correct place for ON in the spectrum of eating and obsessive-compulsive disorders. It will be particularly important to determine whether ON is really anything other than AN, or a variant of AN. There are many obvious similarities. Some of the observed differences, like lack of fear of weight gain in ON, are in fact seen at times in AN. It has also been observed that individuals with ON focus on the quality of food, not quantity; but this, too, is seen at times in AN. Finally, in community samples ON is similarly common in males and females, which does appear to differ from AN samples. However, the gender prevalence ratio of eating disorders in community samples appears to be substantially closer (i.e. 3:1, female to male) (Biol Psychiatry. 2012; 72:164, Arch Gen Psychiatry. 2011; 68:714) than the ratio observed in clinical settings. Thus, this difference in ON vs. AN samples may not be as great as it seems.

— S.C.