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Screens and Your Sleep: The Impact of Nighttime Use

    • There’s a lot of talk about our “addiction” to technology. Aside from the impact of technology on our social lives, what if our cherished devices are bad for our health? When it comes to getting enough restful sleep, it turns out they may be.

      According to Joanna Cooper, M.D., a neurologist with Sutter East Bay Medical Foundation, the timing of sleep and wakefulness is controlled by two areas in the brain. One is highly sensitive to light and drives wakefulness, while the other (the pineal gland) secretes melatonin when the light dims in the evening. Thus we humans are programmed to fall asleep after dark.

      We gradually tamed the dark, first by the use of fire, and later by electric lights. Now we have added another source of light stimulation, in the form of the various screens we stare into – often just before bedtime. The National Sleep Foundation reports that 90 percent of Americans regularly use a computer, TV, cell phone or other electronic device in the hour before they go to bed.

      The particular type of light produced by our technology screens is in the blue part of the light spectrum, the most active in controlling the timing of sleep and therefore suppressing the production of melatonin.

      The light from our screens can delay our transition to sleep, even if we are engaged in some soothing activity online. But it’s more likely that our evening texting, TV shows, or video games are stimulating in themselves, keeping the brain busy and wound up, and even causing adrenalin rushes instead of lullabies.

      So what to do about evening technology?

      • Studies have indicated that an hour of “screen time” at night may be okay, but two or more hours can seriously disrupt the melatonin surge needed for sleep. If you do work into the evening, or use your computer for entertainment, consider switching to another activity in the last hour before sleep, at a minimum.
      • If you must use a gadget with a screen at night, reduce your exposure to the bright light of the computer or cell phone by turning down the brightness in the late evening. There are downloadable programs that can help you adjust screen brightness based on the time of day.
      • Keep technology out of children’s bedrooms (as well as your own.) The American Academy of Pediatrics has taken a stance regarding technology for kids, advising the all electronic devices be removed from children’s and teen’s bedrooms, to ensure no late-night viewing or middle-of-the-night gaming or texting. Their recommendations are concerned not only with sleep, but with rising obesity rates and childhood behavioral issues that may be tracked to too much screen time.

    Ask our experts your health question(s).