By Reneé Prince
Updated March 26, 2021
Over 80% of Americans (1) own a smartphone, and 65% of smartphone owners (2) admit to checking their phone at night. While nighttime scrolling may seem like a harmless activity, doing so could be interfering with your ability to fall asleep and stay asleep.
How Can a Phone Interrupt Sleep?
The body relies on circadian rhythms (3) to know when to initiate sleep versus when to feel awake. The circadian rhythm is a 24-hour biological process that mimics the rise and fall of the sun. A specific part of the brain called the suprachiasmatic nucleus (4) uses external cues such as light to determine if it is time for sleep. At night, the body normally reacts to the darkness by releasing melatonin (5), a hormone that signals that it’s time to sleep.
However, our brains are very sensitive to light, and the blue light (6) emitted from cell phones and other electronic devices delays melatonin production (7). Lack of melatonin can make it difficult to fall asleep, which can lead to insomnia and fatigue over time.
Studies also suggest that blue light can decrease the amount of time the body spends in slow-wave sleep and rapid eye movement (REM) sleep. These two sleep stages are important for consolidating memories and regulating mood (8).
Does Blue Light Affect Children?
Children’s eyes are even more sensitive (9) to light, and the blue light from screens can delay melatonin production by up to two times as much (10) for children compared with adults. This can lead to insomnia and poor quality of sleep, which can be particularly harmful (11) for children.
Quality rest is crucial for children as they grow and develop. Lack of sleep (12) in children can impact academic performance, behavior, and mood. Poor sleep in children has also been associated with health issues, such as obesity (13) and depression (14).
What Are Some Tips for Avoiding Screen Time Before Bed?
Avoiding screens before bed can help children and adults fall asleep faster and get deeper sleep. Some ways to build a technology-free bedtime routine that promotes quality rest include:
- Keeping Your Phone Out of the Bedroom: Having your phone right by your bedside can make it tempting to scroll before bed or when awakened at night. Keeping electronic devices out of the bedroom is one way to avoid the harmful effects blue light has on sleep.
- Using an Alarm Clock: Many people rely on their phones to set an alarm for the morning. However, this can also lead to habitual nighttime scrolling. Consider investing in an alarm clock instead.
- Partaking in a Soothing Activity: Reading a book, drinking tea, or taking a warm bath are ways to wind down without electronic devices. Relaxing before bed without screens can help prepare your body and mind for rest.
- Using Blue-Light Filtering Glasses: Avoiding technology entirely before bed may not be practical for everyone. If you cannot entirely avoid screens before bed, blue-light filtering glasses can be helpful (15). These glasses use special coatings to limit your level of blue light exposure.
While spending time on your smartphone before bed may not seem harmful, it can throw off your body’s natural rhythm and make it difficult to get quality sleep. Making an effort to avoid screens before bed can encourage healthier sleep, which can improve health and quality of life.
- https://www.pewresearch.org/internet/fact-sheet/mobile/ Accessed on March 26, 2021.
- https://www.pewresearch.org/fact-tank/2010/09/13/do-you-sleep-with-your-cell-phone/ Accessed on March 26, 2021.
- https://pubmed.ncbi.nlm.nih.gov/30137792/ Accessed on March 26, 2021.
- https://www.ninds.nih.gov/Disorders/Patient-Caregiver-Education/understanding-Sleep Accessed on March 26, 2021.
- https://pubmed.ncbi.nlm.nih.gov/29318587/ Accessed on March 23, 2021.
- https://pubmed.ncbi.nlm.nih.gov/26900325/ Accessed on March 26, 2021.
- https://pubmed.ncbi.nlm.nih.gov/30311830/ Accessed on March 26, 2021.
- https://pubmed.ncbi.nlm.nih.gov/31071719/ Accessed on March 26, 2021.
- https://pubmed.ncbi.nlm.nih.gov/18757473/ Accessed on March 26, 2021.
- https://pubmed.ncbi.nlm.nih.gov/24840814/ Accessed on March 26, 2021.
- https://pubmed.ncbi.nlm.nih.gov/22114537/ Accessed on March 26, 2021.
- https://pubmed.ncbi.nlm.nih.gov/27040474/ Accessed on March 26, 2021.
- https://pubmed.ncbi.nlm.nih.gov/19955752/ Accessed on March 26, 2021.
- https://pubmed.ncbi.nlm.nih.gov/24497652/ Accessed on March 26, 2021.
- https://pubmed.ncbi.nlm.nih.gov/28045969/ Accessed on March 26, 2021.