Shift workers perform vital tasks whether their work is in hospitals,
in the emergency service, the police force, or in travel,
transportation or manufacturing industries. However, in most cases,
shift workers do not get enough quality sleep. Often it is difficult
for them to remain alert at night, yet just as heard to fall asleep
during the day, and the sleep that they do get is less restorative
than that of night sleepers.
The human body naturally follows a 24-hour period of wakefulness and
sleepiness that is regulated by an internal "circadian" clock. This
clock, which we have in common with all other living creatures and
plants, is linked to natural's cycle of light and darkness, and helps
to regulate body temperature, hormones, heart rate and other
functions. The natural urge to sleep in humans is strongest between
midnight and 6 a.m and it is very difficult it to want to sleep at
other times.
Bright lights and regular sleep wake cycle can help shift workers to
avoid sleep problems and the turmoil they often create. And
melatonin, it appears from much research, can play a supplementary
role. The word supplementary is important: on its own, melatonin is
not remarkably helpful. But as part of a broader program, it provides
real benefits....

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