People in Europe and North America slept the longest, while the shortest sleep was observed among Asians.
The minimum sleep required to sustain a healthy lifestyle varies for different people based on their age, gender and geographical location, says new research.
"It was interesting to find that the circadian rhythm shifts later even in people over 20 years of age. It was previously known that sleep timing is delayed in adolescence. What was clearly highlighted in this study is how long into adulthood this actually carries on," said Liisa Kuula, a post-doctoral researcher at the University of Helsinki who monitored sleeping habits of over 17,000 adolescents and young adults for two weeks.
It was found that people in Europe and North America slept the longest, while the shortest sleep was observed among Asians. Sleep was timed the latest in the Middle East, while the earliest sleep rhythm was found in Oceania.
It was also found that young women slept more than young men, and the former also went to sleep earlier.
"Geographical differences were relatively small but similar to those seen in prior, smaller-scale studies. The need for sleep does not vary greatly between cultures, but differences arise in terms of the time reserved for sleeping," noted Kuula.
The study was published in the Sleep Medicine journal and the monitoring was carried out with the help of Polar Electro devices worn by the study subjects, measuring sleep with accelerometers, among other technologies.
The subjects gave consent for using their personal data for research purposes, with the data being processed in anonymised form.
