For several years, a "night mode" has been available in operating systems from Microsoft and Apple. The objective? Adjust colors to reduce short waves and reduce negative effects on sleep. However, a recent US study concludes that this does not really improve sleep.
We've known it for some time now:blue light from screens affects our eyes. This would be a risk factor for age-related macular degeneration (AMD), a disease of the retina usually affecting people between the ages of 50 and 60. It also plays on melatonin levels (sleep hormone) and thus delays falling asleep. In 2016, Apple launched a night mode in its iOS, a great first. Since then, this option has appeared in other operating systems such as Windows 10 from Microsoft. This allows you to adjust the colors to reduce short waves.
Nevertheless, a study conducted by Brigham Young University in Provo, Utah (USA) and published in the journal Sleep Health April 16, 2021 brings bad news:Night mode doesn't actually improve sleep.
Chad Jensen, lead author of the study, collaborated with researchers at Cincinnati Children's Hospital Medical Center. The team performed sleep quality tests on 167 individuals aged 18 to 24 divided into three categories. The first category related to people using their smartphone at night with night mode activated and the second, without night mode. The last group was made up of individuals who did not use their smartphones at all when going to bed.
According to the results, there was no noticeable difference in the quality of sleep of the three groups. The researchers then reduced the sample to two groups based on previously recorded sleep times. However, the duration of sleep measured in the two groups was between 7 hours and less than 6 in the group having undergone a slight alteration in the quality of sleep. In other words, it is a question of a fairly small improvement which could be attributed to the use of the famous night mode.
The researchers indicated that in all cases, people who did not use their smartphone had a significantly better quality of sleep than the others, but also a longer sleep time. According to the study, blue light is not the only responsible for preventing sleep. The other culprit would simply be the activity on the smartphone itself.
