3 Ways Smartphones are Dumb at Night

Smartphones at night turn out to be pretty dumb, according to research in press from Michigan State University. Russel Johnson and colleagues collected data on business-related smartphone use after 9 pm, sleep, energy, and engagement in work. They found three types of harmful effects from business use of smartphones at night.

  1. Workdays stretching into night. Said Johnson, “when people are using their phones to conduct work late into the night then they’re less able to detach and disassociate from their job.”
  2. Disrupted sleep cycles. They found that using a smartphone for nighttime business was associated with less sleep time and diminished sleep quality. “The kind of blue light given off by these devices seems to interfere with the sleep hormone melatonin. So, there is both a psychological and physiological impact on sleep,” said Johnson.
  3. Diminished  energy and focus. In two separate assessments, they found that bedtime use of smartphones for business was associated with diminished energy, engagement, and focus at work.

Beyond the effects documented in this study, the link of lost sleep and poor sleep quality to obesity is well known. Smartphones keep getting smarter, but the way we use them needs to keep up. Maybe they don’t belong in the bedroom.

Click here to read more from WebMD and here to read an abstract of the research, which is in press here.

Low Battery, photograph © Cristiana Gasparotto / flickr

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