Aliya Zahid, Wajida Tasneem, Rubina Anwar, Farrah Aziz.
Impact of Shift Work on Health: A Review.
Ann King Edward Med Uni Jan ;9(2):70-3.

In modern society, more and more people work during `non-standard` working hours, including shift and night work, which are recognized risk factors for health, safety and social well-being. Unfortunately, humans are physiologically unsuited to inverted schedules, leading to negative consequences for shift workers, employers, and society. The circadian and homeostatic processes which govern sleepiness and alertness are improperly aligned for night workers. Shiftwork, in particular night work, causes disruption of biological rhythms, perturbation of social and family life, with a negative influence on performance efficiency and health. Deterioration of health can manifest in the short-term as sleep disorders and accidents; in the long term there is an increased risk of gastrointestinal, psychoneurotic and cardiovascular diseases, and impairment of the female reproductive function. Night work and rotating shift work disrupt the circadian timing system. This disruption may produce significant deleterious symptoms in some workers. Shift-work scheduling may aggravate certain medical conditions. Vulnerable individuals may develop clinical depression when working shifts.

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