Most experts advise turning off the television and electronic devices well before bedtime to promote better sleep. A new study has found there may be a way to watch television and get good rest too—by wearing blue-blocking glasses.
According to Business Insider, looking at computer screens in bed has been linked to insomnia and to difficulty waking up in the morning in previous studies. Light impacts circadian rhythms and sleep-wake cycles, the authors of the study note.
Light-emitting diode screens give off short-wavelength light, which has been shown to block a natural evening rise in the hormone melatonin that promotes sleepiness. Exposure to this blue light keeps the brain alert and “activated” when it should be slowing down to shift into sleep mode, the researchers say.
For the study, they used orange-tinted “blue-blocker” glasses that filter out short wavelengths of light in the blue portion of the visible spectrum.
For one week, 13 boys between the ages of 15 and 17 wore blue-blocker glasses from 6 p.m. until bedtime each evening, while keeping diaries of how long they wore the glasses and how much time they spent with LED and non-LED screens, as well as a sleep-wake log. They did the same the following week but wore clear glasses.
The teens who wore clear glasses had less melatonin, called the “darkness hormone,” at bedtime. Those who wore the blue-blocker glasses had higher melatonin levels from 90 minutes to five minutes before sleep.
