New research from the U.S. has shed a light on why many night and early morning shift workers have problems sleeping.

A research team at the University of Pennsylvania has discovered that light deprivation hinders the body clock’s ability to regulate the sleep-wake cycle.

It is quite common for shift workers to experience sleep problems because they work when their body needs sleep and vice versa.

The researchers carried out a study with rats and discovered that stronger light intensity allows the neurons which regulate arousal from sleep to function properly and help maintain normal regulation of the sleep-wake cycle, while light deprivation resulted in disruption of the normal sleep-wake cycle.

According to the American Academy of Sleep Medicine increased work space lighting will help night-shift workers’ bodies adapt and make them more alert and effective at work.

They advise workers trying to sleep during the day to ensure that the bedroom is dark to persuade the body that it’s time to sleep.

The National Sleep Foundation offers sleep strategies for shift workers.

The study is published in the October issue of the journal Sleep.