How does screen time affect sleep?

Answers from Eric J. Olson, M.D.

A growing number of studies suggest that use of electronic media, such as computers, TVs, mobile phones or video games, especially before bedtime, is tied to later bedtimes and less sleep for children and adults.

There are many possible explanations for this link. People might simply be using time previously spent sleeping to use electronic media. Or use of electronic media might be displacing physical activity, which generally promotes quality sleep. Another possibility is that the increased physiological and mental arousal caused by electronic devices makes it hard for people to fall asleep.

Some researchers believe that exposure to light at night from electronic media sources can interfere with melatonin, a hormone that helps control the natural sleep-wake cycle. It's also possible, however, that people who have trouble falling asleep might tend to use electronic media before falling asleep. Obviously, further research on this topic is needed.

In the meantime, if you're concerned about the impact of electronic media on your sleep, pay attention to good sleep hygiene. For example, maintain a regular sleep schedule and avoid stimulating light and noise — such as from a TV or computer — around bedtime. If you use your phone or tablet in bed, it might help to turn down the brightness and hold the device at least 14 inches (36 centimeters) away from your face to reduce the risk of sleep disruption.


Eric J. Olson, M.D.

Sept. 28, 2013 See more Expert Answers