By: Dr. Stephanie Bot, C.Psych.
As someone who struggles with sleep, I have been doing a deep dive lately into understanding circadian rhythms and I have come to realize that turning my screens off at night is not something I can take lightly anymore. With fall here and the days growing shorter, many of us feel that shift in our energy, stress levels, and our ability to focus. As we get busier, self-care is often one of the first things we compromise even though it is not a luxury.
Why Light and Circadian Rhythms Matter
Our circadian rhythm operates like an internal clock, governing when we feel alert and when we feel sleepy. Light is its primary regulator. Morning light signals wake up and focus while evening darkness says wind down. Disrupting this cycle, especially with evening screen use, throws the system off, and that can mean trouble for stress, sleep, and productivity.
What Science Shows: Screens, Sleep, and Performance
Here are some sobering statistics about evening screen use and its impacts:
A 2025 study found that each additional hour of screen time after bedtime raises the odds of insomnia symptoms by 59 percent and reduces sleep duration by an average of 24 minutes.
Even for youth, just having a screen device in the bedroom accounts for 30 percent of the variance in sleep efficiency.
Meta analyses show around a 2.17 times higher risk of insufficient sleep and 1.46 times greater odds of poor sleep quality among those using mobile devices at bedtime. They also report 2.7 times more daytime sleepiness.
Among medical students, bedtime smartphone use correlated strongly with poor sleep quality, longer sleep latency, and shorter sleep duration, all of which led to declines in concentration and academic performance. For instance, 82 percent of poor sleepers reported decreased concentration, and 67.4 percent missed classes.
Productivity also suffers. In one observational study, losing just one hour of sleep daily for a week led to performance drops of around 9 percent among both salespeople and athletes, and a 5 percent slower interaction speed with mobile apps.
These numbers tell a clear story. Evening screens disrupt sleep, which then hurts focus, mood, productivity, and stress regulation.
Huberman Labs
If you’re interested in enhancing your wellbeing, I highly recommend tuning into to podcasts by Neuroscientist Andrew Huberman. With respect to light, he emphasizes the transformative power of timed light exposure. A mere ten to fifteen minutes of outdoor light within an hour of waking can significantly boost mood, sharpen attention, and improve sleep that night. On the flip side, he emphasizes that exposure to bright screens in the evening delays melatonin release, making sleep elusive and leaving you less resilient at work. He explains that this impacts not only falling asleep but also staying asleep. Many people comment that they fall asleep fine even though they are using screens before bed but what they do not realize is that the quality and length of their sleep is also impacted by this behaviour.
Practical Steps to Improve Sleep, Concentration and Productivity
You can improve your wellbeing and performance through light savvy habits:
- Morning light exposure: Get outside within an hour of waking. Even on cloudy days, natural light is stronger than indoor lighting.
- Daytime light breaks: Short breaks outdoors in the late afternoon reinforce circadian alignment.
- Evening digital sunset: Dim or power down screens at least an hour before bedtime to protect sleep quality. Ideally, turn all electronics off and engage in other activities such as reading with a reading light. At night it is also better to avoid overhead lighting and use softer lamps or indirect lighting instead.
Why It Matters
Sleep is not optional, it is foundational. When you sleep well, you are calmer under pressure, more emotionally regulated, and more creative. Poor sleep, on the other hand, leads to stress, impatience, and diminished performance.
As the days grow shorter, being intentional with light, especially as it relates to screens, is one of the most powerful and simple tools we have. By sharing these insights with your teams, you help them work brighter, sleep better, and live more resiliently.