How does technology affect my sleep?

  • At night, bright lights can affect the melatonin hormones that help regulate your internal body clock and get you ready for sleep. Bright lights can reduce the amount of melatonin produced and throw your body clock out of whack. As a result, your sleep suffers.
  • Any kind of light can affect these hormone levels, but in particular, the blue light from your devices at night does so more powerfully.
  • Research shows that it may contribute to the causation of cancer, diabetes, heart disease, and obesity.
  • Harvard researchers and their colleagues conducted an experiment comparing the effects of 6.5 hours of exposure to blue light with exposure to green light of comparable brightness. The blue light suppressed melatonin for about twice as long as the green light and shifted circadian rhythms (your internal clock) by twice as much.

What can I do?

  • Use dim red lights for night lights. Red light has the least power to shift circadian rhythms and suppress the melatonin hormone.
  • Avoid looking at bright screens for 2 to 3 hours before bed.
  • If you work a night shift or use a lot of electronic devices at night, consider wearing blue-blocking glasses or installing an app that filters the blue/green wavelength at night.
  • Expose yourself to lots of bright light during the day, which will boost your ability to sleep at night, as well as your mood and alertness during daylight.

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  • Technology use in the evenings may delay bedtime and interfere with sleep.
  • Using a bright screen for 1.5 hours or more can increase alertness.
  • Not all people are affected by technology use in the same way.
  • Some forms of technology use may be better than others and some activities better than others.
  • In the evening, use technology in moderation. Switch from interactive devices (e.g. phones) to passive devices (e.g. e-reader).
  • Data from over 85,000 teenagers (through an analysis of several studies of teenage sleep) showed that different forms of technology use (e.g., televisions, computers, phones – and even video gaming) were related to later bedtimes.
  • The more frequently adolescents used technology in the evening, the later they went to bed.
  • Using technology often may increase alertness and/or reduce the ability to recognise sleepiness at night. Thus the teenagers keep playing, surfing, texting and chatting, resulting in delayed bedtime.

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