With the time change happening this weekend, recent research indicates that adjusting the clocks by one hour in Spring and one hour back in Autumn significantly affects sleep duration, although the impact is brief.
With the time change happening this weekend, recent research indicates that adjusting the clocks by one hour in Spring and one hour back in Autumn significantly affects sleep duration, although the impact is brief.
Conducted by the University of Bristol, the study published today in the Journal of Sleep Research on October 25 analyzed sleep data from 11,800 participants who wore activity monitors during the clock changes between 2013 and 2015. This study is notable for assessing objectively measured sleep patterns in a substantial number of individuals in the UK who are part of the UK Biobank.
It is widely believed that when the clocks move forward an hour in Spring, individuals lose an hour of sleep, while the reverse happens in Autumn when the clocks are set back. Previous studies indicate that it takes people about a week to adjust, leading to reduced sleep for that duration following the time shifts.
This latest research confirmed that on the Sunday of the Spring clock change, individuals indeed slept nearly an hour less compared to the Sundays before and after. However, in Autumn, they did not capitalize on the full hour gained; instead, they only slept approximately half an hour longer than the surrounding Sundays.
The study also observed that the impact of these time adjustments on sleep patterns varied by gender. Men generally caught up on more sleep during the weekdays following both the Spring and Autumn time changes, with a more significant effect noted in Spring. In contrast, women tended to sleep less during the weekdays after the time adjustments compared to before. This may be attributed to higher instances of insomnia and sleep disturbances among women, which can be worsened by the clock shifts.
Despite being temporary, the sleep deprivation triggered by the Spring clock change can have serious health implications, as even a single night of lost sleep is linked to deteriorations in mental and physical health. Furthermore, other research has correlated the act of changing clocks with increased rates of heart attacks, strokes, traffic accidents, and depression.
Melanie de Lange, an epidemiology PhD student funded by Wellcome, associated with the Bristol Medical School: Population Health Sciences (PHS) and MRC Integrative Epidemiology Unit, and a co-author of the study, commented: “As more countries, including the US and EU nations, contemplate ending the practice of clock changes, daylight saving time is sparking significant debate.”
“Our findings contribute to the accumulating evidence that the transition to daylight saving time in Spring leads to a temporary loss of sleep, which could affect the overall health of the UK population. It is essential that any future discussions on the UK’s daylight saving time policy take into account the implications of these time adjustments on sleep and public health.”
