The color blue is considered by many to be beneficial to the mind and body. Being the color of the sky and ocean, it is associated with tranquility and healing. Interior designers often choose blue as a bedroom color because it is thought to promote restfulness and calm.
The irony in this association is that blue, as it pertains to light wavelengths, may actually be the very opposite of restful and healing. Researchers are turning their attention to the effect that blue light has on our sleep and circadian rhythms. And the findings do not paint blue in a positive light. Does blue have a dark side?
Charles Czeisler, Ph.D., M.D. is the Division Chief at Brigham and Women’s Hospital in Boston, MA. He has been researching blue light’s disruptive effect on sleep for some time, and he and his colleagues believe that the effect is profound. Blue is the short wavelength light (found naturally in sunlight) that emanates from most of the artificial light sources and light emanating devices that we encounter all day long and far into the evening. Blue light is linked to the suppression of melatonin, allowing us to remain alert during the day. This prolonged alertness is altering our natural sleep duration. Researchers are discovering that sleep duration has shrunk by an hour and a half over the past 50 years. Some might ask, “What’s the harm in that? I get an extra hour and a half of productivity.” In a meeting facilitated by a Harvard Medical School Media Fellowship, it was said that sixty-nine percent of people report insufficient sleep. Sleep issues are on the rise, from problems falling asleep to challenges staying asleep. Could the cause of the impairment be the artificial light we surround ourselves with? Czeisler thinks so. He’s found that artificial light (specifically short wavelength light like white and blue) can shift our internal clocks by as much as six hours depending on when we are exposed to it. And if you think the solution is just to limit your exposure to a quick peek at the phone, tablet, e-reader, etc., think again. Fellow researcher, Steven Lockley, Ph.D. (Harvard circadian neuroscientist) has documented the disruptive effects of short-wavelength light in a single exposure of less than twelve minutes.
So what advice do these experts have for us? How can we, in a world saturated with blue light, get the rest we need and the maximum health benefits of restorative sleep? Below are a few suggestions culled from various sources:
- Boost your exposure to alerting blue light during the day.
- As evening falls, opt for the warmer wavelengths of lights, such as red or yellow light, to transition your body towards sleep.
- Keep to a regular sleep schedule and a regular meal schedule. Going to bed hungry or eating too much too late at night causes sleep disturbance (and sleep disturbance is associated with weight gain).
- Nicotine, caffeine, and alcohol all negatively impact sleep. Avoid them close to bedtime.
- While fluorescent bulbs are more energy efficient than incandescent, they emit a considerable amount of blue and white light. Limit exposure in the evening, and also limit LED lights, which emit a fair amount of blue spectrum light as well. Use coated fluorescent bulbs that produce a warmer yellow light.
- Use blue-light filters on electronic devices such as your cell phone, tablet, computer, or e-reader.
- Avoid the use of electronic devices (with or without blue-light filters) 2-3 hours prior to sleep.
- Exercise regularly, but not too strenuously prior to bedtime.
- Consider incorporating yoga into your regular routine. It’s been shown to improve sleep in some mind-body therapy studies.
Credit for much of this blog’s content goes to Maria Konnikova for her article, “Why Can’t We Fall Asleep?”, which appeared in The New Yorker magazine on July 7, 2015.