Researchers have found a link between smartphone screen exposure and sleep quality. People who spent more time staring at their smartphone screen tended to have unhealthy sleep patterns and the sleep was of poorer quality. The findings are in a paper that was just published in the journal PLOS ONE.
Smartphones are becoming more and more common in society. Very little research has been conducted on the possible health effects of all of this “screen time”, however. Some researchers believe that screen time can decrease sleep quality. Since poor sleep quality is associated with depression, diabetes, and other health problems, it’s important to fully understand the factors that contribute to poor sleep.
A team of researchers from the University of California collected data from 653 adults that were part of the Health eHeart Study. The Health eHeart Study is a large study conducted over the internet and the participants are all volunteers who chose to participate. Each participant was required to install an app that would track how often their phone’s screen was on. This allowed the researchers to determine an individual’s screen time. This information was compared to both sleep quality and sleep patterns.
The team found that individuals who spent more time looking at their smartphone screens slept less and had lower quality sleep. The average amount of screen time per hour was 3.7 minutes. Participants who had longer screen time than average tended to sleep a lot less, especially when the screen time occurred right before bed. The authors caution that this doesn’t necessarily mean that screen time causes poor sleep. Poor sleep quality could instead lead to increased screen time, for example. In addition, the sample only consisted of self-selected people who reported their own data, further limiting the researchers’ ability to draw conclusions. The team believes that their study should lead to more in-depth investigations since it does show a potential link between sleep and screen time.
The findings suggest that increased screen time may negatively affect sleep quality and the amount of overall sleep. While a single study isn’t enough to prove causation, the team believes that limiting smartphone use before bedtime could be beneficial.
Christensen et al. Direct Measurements of Smartphone Screen-Time: Relationships with Demographics and Sleep. PLOS ONE (2016).