I spend most workdays at the computer. I start at 6:30 in the morning and finish about 7 hours later when my brain runs out of steam. It’s not unusual to spend some or most of the workday on the computer, according to statistics from the Organisation for Economic Cooperation and Development. In 2012, some 64% of working Americans were using computers at work.
In addition to my work-related computer use, I spend an hour or more of leisure time surfing the web and answering emails later in the day. And I wonder: does my heavy computer use increase my susceptibility to insomnia?
A recent article on the relationship between sleep problems and computer use at work and during leisure time offers insight into that. Here’s the scoop:
A Relationship Between Computer Use and Sleep
The researchers took their data from the 2010 Danish Work Environment Cohort Study, a series of questionnaires used to assess the work environment and health and habits of the general working population of Denmark every 5 years. Respondents included 7,883 currently employed wage earners in every major occupation. All worked during the daytime.
The researchers analyzed information about workers’ average weekly computer use at work and their use of computers during leisure time, presumed to occur in the evening. They also used information about workers’ sleep, assessed with questions taken from the Bergen Insomnia Scale. In addition, they took into account several factors that can affect people’s sleep: body mass index and chronic health conditions, for example; work conditions, such as demands made of workers and their influence at work; and workers’ level of physical activity on the job and during leisure time.
Sleep Effects of Computer Use at Work
Even after investigators controlled for all the variables, their results showed no relationship between work-related use of the computer in the daytime and the soundness and quality of workers’ sleep at night. So I guess I can’t blame my insomnia on my 7 or 8 hours of screen time!
(Take note, though: excessive screen time is known to have other harmful effects, including eye strain, dry eyes, and blurred vision. Also, the heavy use of blue light-emitting devices with screens may have more serious long-term effects such as the earlier formation of cataracts and macular degeneration.)
Sleep Effects of Computer Use During Leisure Time
Light or moderate use of the computer during leisure time had no effect on workers’ sleep at night. But workers who spent 30 or more hours a week (that’s an average of between 4 and 5 hours a day) on the computer in their free time were almost twice as likely to have severe sleep problems as those whose leisure-time computer use was more limited—even after adjusting for all the confounders listed above.
Other studies have shown that, used at night, computers and other devices with screens interfere with sleep. The usual explanation is that the light they emit blocks secretion of the hormone melatonin, thereby delaying sleep onset. The psychological arousal associated computer gaming, use of social media, and/or working at night to meet tight deadlines might also contribute to the sleep problems of those who spend lots of time on the computer at night.
But the take-away here, the authors conclude, is that any negative effect of light from the computer screen on sleep is relatively short lasting. It’s heavy use of computers at night that might cause you to experience insomnia—not being married to the computer during the day.
How many hours a day do you spend on the computer? Have you noticed it affects your sleep?