Abstract
Measuring orthorexia nervosa is challenging due to the use of various existing tools and problems with sample representativeness. Another challenge for the Polish population is the adaptation of existing research tools and the evaluation of their relevance and research reliability. Our research aimed to adapt the TOS to the Polish language and measure pathological and nonpathological orthorexic behavior among the Polish population. The adaptation of the PL-TOS has high psychometric value and allows us to assess healthy and nervous orthorexia levels. This scale can be used not only for further research but also for diagnostic purposes in the daily work of clinicians and psychologists. Our results obtained in the present study indicate a correlation between TOS and both the use of supplements and diet. Higher TOS, ORTO_R and KZZJ_Diet Restrictions scores were obtained for individuals using dietary supplements than for those not using dietary supplements. In the future, it is worth conducting research aimed at various risk groups of individuals with orthorexia to confirm the psychometric properties of this adaptation of the TOS.