Blue light and sleep

Blue light pollution

Do you have trouble getting to sleep at night, and then feel sleepy and groggy in the morning?

“Blue light” from your TV, phone or tablet might be to blame. Do you watch TV or sit at your computer just before bed? Or take your phone, laptop or Kindle into bed with you?

These electronic devices all emit what’s known as blue light. Blue light is a specific part of the light spectrum. It’s why the sky is blue, and so our brains naturally associate blue light with day and become more alert, even if it’s time for bed.

Our bodies’ natural sleep rhythms started becoming disrupted as soon as Edison introduced the light bulb. Suddenly, our sleep patterns were no longer limited to the seasons and the daily rise and set of the sun.

But the explosion of personal technology—computers, game consoles, iPads, iPods and iPhones—in the last ten years has been especially disruptive.

Melatonin is the hormone our brain secretes to help us get to sleep. Blue light interferes with melatonin production, and it isn’t until we’ve tossed and turned well into the night that our melatonin level increases enough to make us sleepy. But that’s just when we need to get up and start a new day!

Lights out for better sleep

In his book Sleep Soundly Every Night, Feel Fantastic Every Day, Dr. Robert Rosenberg offers the following advice:

  • Turn off communication/entertainment devices two hours before bedtime.
  • Use a red or orange light in the bedroom, as these light waves interfere least with melatonin production.

And if you just can’t give up your late-night gadget habit:

  • Wear blue light blocking glasses at night.
  • Install an app (f.lux) on your phone, tablet and computer that alters the color of your display according to the time of day. Here’s the link:

The newer generation of compact fluorescent and LED light bulbs emit more blue light than regular incandescents. I don’t have a red light bulb in my reading lamp, but I do have a low-Watt (40W) incandescent bulb.

Blue-light blocking glasses are relatively inexpensive and Dr. Rosenberg says they work for his patients.

If you have prescription glasses with the anti-glare or anti-reflective coating, they probably already block blue light.

I haven’t tried f.lux, but my son has used it on his computer for several years and says it runs in the background without any problem. Whether it has helped with his sleep patterns, or not, he can’t say.

Blue light isn’t responsible for all our sleep issues. But eliminating or mitigating it before bedtime is at least a good place to start if you are looking for a better night’s sleep.


Frugal Nurse

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