[SHIFT WORK AND ITS HEALTH HAZARDS].

INTRODUCTION: Work in repeated changing shifts, in general, and night-shifts, in particular, is considered a necessity, encompassing many professions, among them physicians and nurses. This type of work has been shown to adversely affect the normal function of the human body circadian rhythm. This negative influence in turn, is considered to increase characteristic types of morbidity such as metabolic syndrome, type 2 diabetes and increased rate of cardiovascular morbidity. Women working in night-shifts in particular, have been found to face increased rates of breast cancer, as well as menstrual disturbances and decreased fertility. Despite many physiologic explanations for the deleterious effects of changing or night-shifts on human's health, there is no clear notion for the prevention or treatment of these health hazards. In light of the necessity for such a mode of employment in our modern world, the issues of taking care of the affected workers should be considered on a national scale.