You design a bedroom where you hope to relax and fall gently to sleep. Give the space you’ve created the chance to work, as planned. Don’t use your smartphone after 9 pm for business.

Johnson, Lanaj, and Barnes and have learned that “Using a smartphone to…work at night results in less work the next day… People [participating in a research study] who monitored their smartphones for business purposes after 9 p.m. were more tired and were less engaged the following day on the job… ‘They keep us mentally engaged late into the evening, they make it hard to detach from work so we can relax and fall asleep’ [said study co-author Johnson of Michigan State]… In addition to keeping people mentally engaged at night, smartphones emit ‘blue light’ that seems to be the most disruptive of all colors of light. Blue light is known to hinder melatonin, a chemical in the body that promotes sleep.”

The negative effects of smartphones on sleep were more significant than those of watching television and using laptop/tablet computers.

Don’t let yourself be tempted—unless you’re waiting for truly important news, don’t let your smartphone spend the night in your room. Not bunking with your phone will make your life a whole lot better.

“Nighttime Smartphone Use Zaps Workers’ Energy.” 2014. Press release, Michigan State University,

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