Digital Sunset

Cutting screens 60–90 minutes before bed is one of the highest-leverage sleep interventions available without any cost.

What it is

A digital sunset is a deliberate cutoff time for screens — phones, laptops, tablets, television — in the evening, typically 60–90 minutes before bed. It addresses the twin problem of blue light suppressing melatonin and the psychological activation from social media, news, and notifications keeping the mind in alert mode.

Why it matters

Blue light in the 480nm range suppresses melatonin production by signalling the SCN that it is still daytime. This delays sleep onset and reduces total slow-wave sleep. But the content problem is equally important: notifications, upsetting news, and the endless novelty of social media activate the dopamine system and keep cortisol elevated. For someone going through cancer treatment, who is already carrying enormous cognitive and emotional load, the evening environment before sleep is critical real estate. The digital sunset protects both the hormonal preconditions for sleep and the psychological state needed to enter it.

The evidence

A 2015 Harvard study found that evening e-reader use (vs. printed books) delayed sleep onset by 10 minutes, reduced melatonin by 55%, and reduced next-morning alertness. A large 2019 JAMA Pediatrics study confirmed evening screen use disrupts sleep onset and quality. The American Academy of Sleep Medicine explicitly recommends no screens 30–60 minutes before bed; most sleep researchers advocate for 90 minutes.

This information is for educational purposes and does not constitute medical advice. Always discuss lifestyle changes with your care team, particularly if you are undergoing active cancer treatment.

How to practice

Set a consistent alarm for your digital sunset — 90 minutes before target sleep time. At that point, phones go face-down or on airplane mode. Replace the time with non-activating activities: reading physical books, light stretching, journaling, conversation, or body scan meditation. Use warm, dim lighting in the evening (lamps rather than overhead lights, ideally amber-tinted). On difficult nights when anxiety makes stopping devices hard, note that scrolling likely increases anxiety, not reduces it — choose the physical book anyway.

Frequency

Daily, 60–90 minutes before sleep

Notes

Blue-light-blocking glasses are a partial mitigation if you must use screens in the evening, but they do not address the content activation problem. Do not use the phone as an alarm clock if it lives on your bedside table — buy a separate alarm clock so the device leaves the room.