Smartphone use at night may not be that harmful: Study

Do you love to read e-books on smartphones or tablets late at night but are worried about the negative results of the blue light exposure? Take heart, as according to a study, ample exposure to daytime light may help combat sleep disturbances associated with the evening-time use of electronic devices.

The findings showed that daytime bright light exposure, by means of outdoor activities or light interventions in offices, did not affect sleep in young healthy students who used a self-luminous tablet for two hours in the evening time.

"Our most important finding was that the issue of whether screen light in the evening could interfere with your sleep is more complex than previously highlighted and that there are certain important factors (such as daytime exposure to light) that affect this," Frida Rangtell, doctoral student at Uppsala University in Sweden, was quoted as saying to the thelocal.se.

The levels of melatonin -- the hormone affecting sleep-wake cycle in humans -- were found have no significant adverse effects.

"However, it must be kept in mind that utilising electronic devices for the sake of checking your work e-mails or social network accounts before snoozing may lead to sleep disturbances as a result of emotional arousal," explained Christian Benedict, Associate Professor at Uppsala University.

The use of smartphones and tablets during evening hours has previously been associated with sleep disturbances, as well as blindness, the researchers noted.

According to a study published in The New England Journal of Medicine, two women were affected by transient smartphone "blindness" in one of the eyes as a result of gazing into smartphone before they slept.

For the current study, published in the journal Sleep Medicine, the team compared the effects of bedtime reading using a tablet versus an actual book in 14 young women and men from Sweden for better or worse.

The team asked the participants to read from 9 pm to 11 pm, with one half of the group using a tablet and the other half a normal book.

There were no differences in sleep parameters and pre-sleep saliva melatonin levels between the tablet reading and physical book reading conditions.

--IANS

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