Using a computer tablet with a backlit screen can lead to sleepless nights and an increased risk of sleep disorders, according to a new study from Rensselaer Polytechnic Institute’s Lighting Research Center, because the technology suppresses the sleep hormone melatonin.
Prof. Mariana Figueiro, who headed up the study, summarized the research findings as follows:
“Our study shows that a two-hour exposure to light from self-luminous electronic displays can suppress melatonin by about 22 percent. Stimulating the human circadian system to this level may affect sleep in those using the devices prior to bedtime.”
Only 13 subjects — who read, played games, and watched movies on their tablets — participated in the study, however, so it’s likely that the experiment needs to be replicated with a larger ensemble.
If valid, the results could be particularly a problem for teens and the under-30 cohort, groups that typically keep late hours as it is. Study co-author Brittany Wood explained the ramifications:
“Technology developments have led to bigger and brighter televisions, computer screens, and cell phones. To produce white light, these electronic devices must emit light at short wavelengths, which makes them potential sources for suppressing or delaying the onset of melatonin in the evening, reducing sleep duration and disrupting sleep. This is particularly worrisome in populations such as young adults and adolescents, who already tend to be night owls.”
Prof. Figueiro suggested that technology manufacturers need to produce more “circadian-friendly” devices that adjust the screen lighting for the time of day. In the meantime, she recommends “dimming these devices at night as much as possible in order to minimize melatonin suppression and limiting the amount of time spent using these devices prior to bedtime.”
The study, which was published in the Applied Ergonomics journal, also ominously notes that “melatonin suppression by light at night has been linked to diseases such as cancer.”
Is your computer tablet or another electronic gadget keeping you up at night?