- Increased screen exposure before bed can affect sleep quality.
- The COVID-19 lockdowns saw an increase in the use of electronic devices.
- New evidence suggests that the increase in screen exposure during the COVID-19 lockdowns may be linked to worse sleep quality.
All data and statistics are based on publicly available data at the time of publication. Some information may be out of date.
In many European countries and the United States, COVID-19 lockdowns began in March 2020. The Imperial College London COVID-19 Response Team and others proposed that having people stay home would help limit the spread of the virus.
Governments instituted lockdowns to try to prevent a catastrophic number of deaths and ensure that hospitals did not become overwhelmed. Nonessential businesses closed, people stayed home, and schools utilized online learning methods.
However, the lockdowns led to new problems regarding other areas of health and well-being. One such area was sleep hygiene.
According to a recent longitudinal study, which now appears in the journal Sleep, sleep quality declined during the COVID-19 lockdowns. The study examined increases in screen use during the lockdowns and how this negatively affected sleep quality.
Sleep impacts many areas of health. Getting enough quality sleep helps people feel rested, but sleep also contributes to our ability to learn and form memories, recover from injuries, and fight infections.
Not getting enough sleep or having poor sleep quality can contribute to the onset of many physical health problems, such as high blood pressure, type 2 diabetes, heart disease, stroke, kidney disease, and obesity.
Karl Rollison, a professional life coach and registered hypnotherapist, told Medical News Today, “When we sleep well, we feel well; we experience improved vitality, concentration, productivity, and mental resilience.”
“Quality slumber is the body’s opportunity to repair damaged cells and flush out harmful toxins, leaving us feeling refreshed.”
When people use screens before bed, it can have a negative impact on their sleep quality. As the National Sleep Foundation notes, there are several reasons for this:
- Screens such as those on smartphones emit blue light, which can increase feelings of alertness.
- Engaging activities such as texting or playing games increase brain stimulation.
- Engagement in certain content can elicit emotions that make it difficult to relax.
Electronic use can disrupt sleep, such as when a text alert wakes someone up in the middle of the night, and delay when people actually fall asleep, such as when they feel the need to reply to one more message or play one more game.
Rollison explained it this way: “Like any process, the clearer the instruction given, the more efficiently a system will operate. Our 24-hour sleep/wake cycle is controlled by a part of our brain called the suprachiasmatic nucleus (SCN). It monitors environmental light levels and produces varying degrees of the sleep hormone melatonin accordingly.”
“The darker the environment, the more melatonin we produce and the better we sleep. Light emitted from electronic devices [confuses] the SCN with vague, contradictory signals, which results in sleep disruption.”
Research about how the use of electronic devices impacts people’s sleep quality is ongoing. The COVID-19 lockdowns saw a new social situation with an immense increase in the use of electronic devices.
The researchers behind the new study hypothesized that this increase may be linked with a decline in sleep quality.
The study, which the researchers conducted using data from Italy, examined how increased screen exposure during the COVID-19 lockdowns affected sleep quality.
In Italy, there was a total lockdown in place from March 9 to May 4, 2020. It required most of the general population to stay home.
The COVID-19 lockdowns saw a dramatic increase in the use of the internet and electronic devices. This was related to multiple factors, such as the increased use of video calls replacing in-person meetings and an increase in the number of people working from home.
The researchers note that this increase was likely because people were trying to compensate for limited social interaction and fill up new free time.
The study involved 2,123 participants and used several surveys to evaluate sleep quality during the third and seventh weeks of lockdown.
The first round of surveys used the Pittsburgh Sleep Quality Index and the Insomnia Severity Index to evaluate the participants’ sleep quality and identify problems with insomnia. A person may have insomnia if they have difficulty falling or staying asleep.
The participants provided information related to their demographics, and the scientists gave them the option to fill out several questionnaires related to anxiety, depression, and perceived stress. The researchers note that these factors normally affect sleep quality, and they sought to account for them in their findings.
The second round of surveys included all previous surveys but with one additional question. The new question asked if the participants had increased, maintained, or reduced their screen time in the 2 hours before bed since the time of the initial survey.
The study found a decline in sleep quality for people who increased their screen time exposure in the 2 hours before bed. In contrast, those who reduced their screen time in the 2 hours before bed reported an improvement in sleep quality.
Contributing study author Prof. Michele Ferrara summed up the results to MNT:
“Our results showed that respondents who increased screen time (35.4% of participants) reported decreased sleep quality, exacerbated insomnia symptoms, reduced sleep duration, prolonged sleep onset latency, and delayed bedtime and rising time.”
“Conversely, respondents reporting decreased screen exposure (only 7.1% of participants) exhibited improved sleep quality and insomnia symptoms. Finally, participants preserving screen time habits did not show variations of the sleep parameters.”
However, the study did have limitations. For example, it could not prove that increased screen time before bed caused a reduction in sleep quality. Other limitations included the population sample, which had a higher prevalence of women and young people and did not include adolescents.
Also, screen time data relied on self-reporting from the participants and did not measure how large the increase or decrease was for each participant.
Similarly, the scientists could not assess the impact of different types of electronic devices and other factors, such as room lighting or the use of blue light-blocking glasses.
The authors agree that more research is necessary to look at these factors and how they affect sleep.
Nevertheless, the researchers note that the study’s findings line up with previous data about the impact of electronic device use on sleep quality. Prof. Ferrara notes:
“The evidence of a strong relationship between screen habits and the time course of sleep disturbances during the lockdown period suggests that […] raising public awareness about the risks of evening exposure to electronic devices could be crucial to preserve general sleep health. This applies to both the ongoing pandemic and the future, as technologies will find more and more space in our daily routine.”