News Release

What happens to our online activity over the switches to and from Daylight Saving Time?

Peer-Reviewed Publication

University of Surrey

Researchers noticed that after switching to DST, certain Google searches took place up to an hour earlier than usual. On the other hand, when clocks went back to standard time in autumn, these searches tended to occur later. 

 The shift in search times varied across different search categories. Notably, the time of searches around sleep and health varied by less than 60 minutes over DST changes, hinting at a strong and robust role of the internal body clock in driving them. 

 Professor Sara Montagnese, co-author of the study from the University of Surrey, said: 

"Our research calls for wider discussions about the health and wellbeing impact of DST and the complex relationship between our internal body clock and the time constraints imposed by society, which are collectively known as the “social clock”, of which DST is part." 

 Researchers analysed Google Trends data from Italy, covering 2015 to 2020. The team examined the relative search volume for 26 keywords, grouped into three categories: 

  • Sleep/health-related: includes search terms related to sleep patterns, sleep disorders, and overall health concerns. Terms such as “insomnia” and “melatonin” fall under this category. 

  • Medication: this category includes terms concerning drugs and pharmaceuticals. Terms like “painkiller” and Xanax” are included in this category.  

  • Non-sleep/health-related: this category covers terms that are unrelated to sleep or health. Examples include “spa” and “taxi”. 

The study has been published in the Journal of Circadian Rhythms. 

Notes to editors

  • For more information, please get in touch with the University of Surrey's media office via

Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.