Night Shift mode is a built-in software on iOS and macOS which shifts the color temperature of the display towards the yellowish part of the color spectrum. It claims to filter blue wavelengths from the display but does it actually work?
An article in press set to be published in Sleep Health (Duraccio et al 2021) investigated these claims by comparing sleep latency, duration, efficiency, and wake after sleep onset in adults. They compared three groups (167 total subjects) in the hour before bed:
- iPhone use with Night shift
- iPhone use with Night shift disabled
- No phone use
What did the results show?
No difference in sleep outcomes could be attributable to Night Shift
For individuals obtaining adequate sleep (> average 6.8 hours) those abstaining from screen time had the best sleep quality.
This study raised an extremely important point, which is that night shift may not offer the protective effect that many assume it has for preserving sleep quality. Whether that is because it isn’t actually filtering all of the blue light or the activity of being on the phone itself is activating we can’t say for sure. The bottom line from this study is that it is best to put the phone away one hour before bedtime.
Do you use the Night Shift mode in the hopes of getting better sleep?