Disorders of food intake belong to serious medical diseases at the child and adolescent age. The most prominent symptom is changed body mass – obesity or malnutrition (e.g. in mental anorexia), which influence almost all physiological functions of the organism including activity of autonomic nervous system. At the present time there are few papers dealing with the problem of mental anorexia and changes in autonomic nervous system. Bradycardia with increased parasympathetic activity is a typical finding in mental anorexia and may decrease significantly or even abnormally after some time. The conclusions concerning the evaluation of sympathetic activity are not unambiguous. The determination of changes in the activity of sympathetic and parasympathetic part of autonomic nervous system presently employs linear and nonlinear methods for analysis of variability in heart rate and blood pressure as well as the examination by cardiovascular tests. It is also for the increasing rate and severity of food intake disorders at the child and adolescent age that monitoring of the changes in autonomic nervous activity should be continued and the effects of therapy and therapeutic procedures should be investigated.

        Key words: autonomic nervous system,mental anorexia, heart rate variability, blood pressure variability, cardiovascular system reactivity