Dear Health-conscious Friend,
How Being a “Light Sleeper” Can Be a Good Thing
I’ve written about light and sleep before. The screens from cell phones, tablets, computers and TVs give off a lot of blue light. Using these devices before bed can throw your sleep-wake cycle off… and leave you tossing and turning at night.
Now studies are revealing how to use your body’s reaction to light to improve your sleep.
University scientists from Illinois discovered getting the right light at the right time of day can help you sleep better at night.
The researchers compared the work conditions of 49 workers – some of whom worked in windowless rooms. Others worked in bright, naturally lit offices.
The windowless group didn’t sleep as well and suffered more sleep disturbances. The group working in well-lit areas was more physically active and slept better.1
Meanwhile, a study published in the journal Sleep offers a way to be more effective when you have a rough night. Just get more blue light.
In this small study, people exposed to blue light during the day were more alert, paid closer attention and more responsive than people exposed to redder wavelengths of light.
The study also confirmed blue-light exposure interferes with the normal sleep-wake cycle, if you’re exposed at nighttime. But daytime exposure doesn’t appear to have a negative effect.2
A third study found that red light can help you get through the afternoons doldrums.
Lots of people struggle through the mid-afternoon blahs. A couple of hours after lunch, you just start to crash… you become tired, sleepy and lethargic. Instead of reaching for a coffee or a candy bar, look for a source of reddish light.
Volunteers I this study showed much weaker brain waves linked to sleepiness when they were exposed to red light mid-afternoon. They also remained more alert.3
To help you sleep better, here’s another little trick with light. Try dimming the lights at suppertime.
Doctors at Northwestern University discovered that blue light can make you hungrier. Exposure to blue light took about 15 minutes to increase evening hunger. And the subjects continued to feel hungrier than normal for about 2 hours after eating.4
Since eating a heavier evening meal can make it harder to sleep, enjoying more candlelit dinners could prove more than just romantic.
Yours in continued good health,
Dr Kenneth Woliner, M.D.
1 Boubekri, M., et al, “Impact of Windows and Daylight Exposure on Overall Health and Sleep Quality of Office Workers: A Case-Control Pilot Study,” J Clin Sleep Med 2014; 10(6): 603-611.
2 Rahman, S.A., et al, “Diurnal Spectral Sensitivity of the Acute Alerting Effects of Light,” Sleep 2014; 37(2): 271-281.
3 Sahin, L. and Figueiro, M.G., “Alerting effects of short-wavelength (blue) and long-wavelength (red) lights in the afternoon,” Physiology & Behavior. May 27, 2013; 116-117: 1-7.
4 “Study links evening blue light exposure to increased hunger,” American Academy of Sleep Medicine. Jun 2, 2014.