In this technological society, most people love the comfort of their screens. Devices are used at all hours of the day and night. Who hasn’t crawled into bed with their phone, tablet, or watched a movie on their flat screen before sleep? However, new research out of the University of Houston College of Optometry showed that the blue light emitting from these devices might be contributing to the increasing prevalence of sleep dysfunction. Findings were reported in Ophthalmic & Physiological Optics.
The study participants were aged between 17 and 42 years, each of whom more special short wavelength-blocking glasses for two weeks. They put them on three hours before bed and performed all their usual nightly digital routines. Melatonin levels increased by 58% in these participants. Melatonin is a natural hormone that tells your body when it’s time to sleep. Dr. Lisa Ostrin from the UH College of Optometry was the lead author of the study. She notes that this increase is more than what is seen on someone who takes over-the-counter melatonin.
The most important finding in this research was that the blue light at night decreases quality of sleep. Sleep is vital for the body’s restoration and regeneration processes.
Twenty-two participants wore 24/7 sleep and activity monitors. All of them reported falling asleep faster, sleeping an average of 24 minutes longer, and sleeping better.
The sun is the biggest blue light emitter; however, nearly every LED-based device also uses blue light. This light helps the mind stay alert and regulates the internal biological clock, or circadian rhythm. This clock tells the body when it’s time to sleep and wake. The artificial lights from devices activate photoreceptors (ipRGCs) that suppress melatonin.
Dr. Ostrin makes several recommendations:
The special blue-light-blocking glasses help to decrease the photoreceptor input, which will make it easier to improve while continuing to use the devices.
Surveys show that three-quarters of Americans are satisfied with their sleep on any given week; however, about 4 in 10 people report that they see significant changes in their daily activities when they don’t get enough or decent quality sleep.
© 2021 American Sleep Association.