Shift WorkerReferring to the WHO's definition of "health", shift work is a risky condition at all the three reference levels, as it is not only a risk factor for many health disorders (e. g. gastrointestinal, psychoneurotic, cardiovascular, reproductive functions, and probably cancer), but it also perturbs psycho physical homeostasis (e. g sleep wake cycle and circadian rhythms) and hampers family and social life. This is why it is imperative to have good sleep