Your Smartphone May Be Hurting Your Sleep
A) You love your smartphone, but it may be ruining your ZZZ’s. Use of these devices, especially near bedtime, is associated with worse quality of sleep, according to a new study. “When we looked at smartphone use around the time when participants reported they went to bed, more smartphone use around that time in particular was associated with a longer time to fall asleep and worse sleep quality during the night,” said Dr. Gregory Marcus, author of the study and an associate professor of medicine at the University of California, San Francisco. His research was published Wednesday in the journal PLOS One.
B) The word “crack-berry” became popular roughly a decade ago to describe the addictive quality of BlackBerry devices—arguably the first really successful smartphones. Today, almost everyone is a smartphone junkie, standing with head bowed while waiting for a train or in line at the post office.
C) Knowing that smartphone use has increased together with sleep deprivation rates, Marcus and his colleagues decided to investigate whether the two might be related. To answer this question, he used exiting information collected by an Internet-based study he started in March 2016.
D) “Health E-Heart,” which was funded by the National Institutes of Health is designed to study cardiovascular health. Anyone 18 years of age or older can enroll in Health E-Heart, co-founded by Drs. Mark Pletcher and Jeffrey Olgin, professors at UCSF. After signing a consent form, enrolled participants self-report their health data via a series of online questionnaires. The information is gathered, analyzed and used to research and develop strategies to prevent and treat all aspects of heart disease.
E) About 80,000 participants have enrolled in Health E-Heart, Marcus said. “We’ve had people from every state in the US, lots of people from every state, and we actually have people from 50 countries.” Marcus and his co-founders also make the data available to other scientists conducting unrelated studies. For the new smartphone study, Marcus made use of this wealth of information to conduct his own “sub-study”.
F) Of the total Health E-Heart enrollees, 653 people chose to participate in and complete the new smartphone-sleep study. Participants installed an app on their phones to automatically record the total number of minutes in each hour the screen was turned on (total screen time) during a 30-day period. These participants had already reported their sleep hours and sleep quality using a validated questionnaire as part of the general Health E-Heart experience, Marcus explained. So, when answering the sleep assessment questions, participants also entered demographic data plus information about their alcohol use, physical activity, smoking habits and other health issues. By answering so many questions, participants were unaware of what the researchers were studying, explained Marcus: “We wouldn’t expect any bias.”
G) Analyzing the data, the researchers discovered that, on average, participants used their smartphones for a total of 38.4 hours over a 30-day period. Individuals with a longer average screen time were more likely to have poorer sleep quality and less sleep overall: About 35% of those who used their smartphones for shorter amounts of time than average had sleep difficulties, compared with 42% of those with average or greater than average use. And poor quality sleep was more likely for participants who used their smartphones near bedtime.
H) The researchers discovered that screen-time varies throughout a 24-hour period, but most occurs during the day. Yet for some participants, smartphone use peaked during the night. “We can’t exclude the possibility that some people can’t sleep for some completely unrelated reason, and because they can’t sleep, they’re using their smartphone, just to pass the time,” Marcus said.
I) Despite potential shortcomings, Marcus research is in line with other studies showing that the use of technology near bedtime is associated with difficulty sleeping, such as the 2015 National Sleep Foundation poll. Other research has shown that the blue light emitted by smartphones (and other digital devices) might suppress our body’s production of melatonin, a hormone that induces tiredness and contributes to the timing of sleep-wake cycles. “So there’s some biological plausibility supporting the idea that there is a causal relationship, but we weren’t able to identify that,” Marcus noted.
J) “It is believed that sleep is a restorative process and a basic biologic need,” said Dr. Neil Kline, a sleep physician, internist and representative of the American Sleep Association. “When animals, including humans, are deprived of sleep, there are many body systems that fail. Not only does our performance, memory and attention span suffer, our immune system and endocrine system is also impaired.”
K) Though most of these negative effects have been studied exclusively in adults, children’s sleep is also affected by technology, according to an unrelated study. Lead author Ben Carter, a senior lecturer in biostatistics at King’s College London, and his colleagues discovered that for teens and children, the use of cell phones, tablets and computers is associated with losing sleep time and sleep quality.
L) Marcus said he suspects that some people may be affected more than others and overuse of a smartphone impacts their sleep more than it would for other people. He hopes to investigate this question in the future. Based on his results, he suggested that insomniacs and other troubled sleepers should avoid looking at their screens for half an hour or so before going to bed to see whether that might enhance the quality of their slumber. He added, “There’s almost certainly no harm in giving that a good try.”
11. Our addiction to smartphones dates back to about ten years ago. _________
12. Data from Health E-Heart are collected and used for researchers into heart diseases. _________
13. The findings of Dr. Marcus’s study appeared in PLOS One. _________
14. Bad sleepers are advised not to use their smartphones half an hour or so before they go to bed. _________
15. Marcus started his research because he suspected there might be some correlation between sleep loss and smartphone use. _________
16. The use of digital devices affects children’s sleep too. _________
17. To make sure his study was objective, Marcus required his subjects to provide many more of their life details than just sleep hours and sleep quality. _________
18. Researchers found those who spend longer time playing with their smartphones are more likely to sleep badly. _________
19. Marcus conceded that some people were sleepless at night for reasons unrelated to mobile phone use. _________
20. Sleep is our basic biological need and lack of it may cause our body functions to decline. _________
