Objectives:
Shift work is more harmful for the body than full time work during daytime – it prevents employees from keeping the natural, physiological human circadian rhythm. As many as 70% of employees working in a shift system are unable to define precisely the level of intolerance to this type of work. The aim of the study was to recognize health behaviours among nurses working in a shift system according to age, as well as to discover whether there is any relationship between the hospital ward of employment and particular health behaviours.

Material and methods:
The research was conducted in the District Hospital in Wadowice. A total number of 133 nurses working in a shift system participated in the study. A diagnostic survey was carried out in order to collect information using questionnaires applied in psychological research in the field of health psychology – Health-Related Behaviour Inventory by Zygfryd Juczyński.

Results:
The mean value of correct eating habits observed in the study group was M = 3.37, followed by prophylactic behaviours - M = 3.36, a positive mental attitude - M=3.38, and health practices - M = 2.87. An overall rate of intensity of health behaviours in the study group was M = 77.87. The type of workplace did not exert any statistically significant effect neither on prophylactic behaviours nor on positive mental attitude.

Conclusions:
Nurses working in a shift system represented a mediocre level of undertaking health behaviours. The highest level and intensity of health behaviours was observed in those who worked in the Operating Block. The more advanced the age of the nurses, the more frequent correct health behaviours. Considering the low level of undertaking health behaviours by the nursing staff it is necessary to involve hospital management in the preventive measures.