Introduction:
The term orthorexia nervosa was coined in 1997 by American physician Steven Bratman. Orthorexia is considered when daily activities are subordinated to time-consuming planning, buying and preparing meals.

Objective:
The main aim of the study is presentation of the problem of orthorexia as a relatively new and unknown eating disorder. The article also presents the methods of diagnosis and treatment, as well as the groups at-risk for this disorder.

Brief description of the state of knowledge:
The exact number of people suffering from orthorexia is unknown. This is probably due to the fact that patients rarely admit that they have a problem with eating, and even more so, they do not report to specialists for treatment. There is also a lack of uniform definition and diagnostic criteria. It combines the features of eating disorders, obsessive compulsive disorder and somatoform disorders. Features that support the diagnosis of orthorexia are: excessive attachment to a healthy lifestyle, the presence of obsessive-compulsive personality traits and rigidity of behaviour associated with the preparation of meals, as well as the occurrence of negative consequences resulting from the maintenance of this behaviour. Unfortunately, these behaviours carry dangerous consequences: from malnutrition and nutrient deficiencies, due to a restrictive and not very varied diet, to disorders of social functioning caused by isolation and fear of judgement by the environment.

Conclusions:
There is a very thin line between looking after rational nutrition and obsession on it. All issues related to or-thorexia presented in the article clearly indicate that despite the lack of a uniform definition and diagnostic criteria, it should not be underestimated.