New research published in the Proceedings of the National Academy of Sciences has shown that the amount of sleep required for positive health outcomes varies significantly between locations and cultures, challenging the common belief that all people need around the same amount of sleep.
The study included sleep duration and health data from nearly 5,000 people in 20 different countries. Many previous studies have shown that shorter sleep durations are associated with negative health consequences (including higher risk of cardiovascular problems), and some past studies have also shown that sleep duration varies significantly between cultures and locations. The objective of this study was to determine whether people from locations and cultures with shorter sleep durations tend to have worse health outcomes than people from countries and cultures with longer sleep durations.
The results showed that people from cultures with shorter sleep durations did not suffer from worse health conditions than those from cultures with longer sleep durations. The perceived optimal amount of sleep varied between different cultures, and people whose sleep duration was closer to their cultural ideal tended to enjoy better health. For example, the average amount of sleep in Japan was 6 hours and 18 minutes per night, in France it was 7 hours and 52 minutes per night, and in Canada it was 7 hours and 27 minutes per night. Interestingly, across all 20 cultures, the average amount of sleep per night was about an hour less than the perceived ideal amount of sleep. In each country, getting closer to this ideal amount of sleep was associated with better health outcomes.
The authors noted that there is no “one-size-fits-all” in terms of ideal sleep duration, despite the common advice to aim for 8 hours of sleep per night. Instead, sleep recommendations should be adjusted based on cultural norms. Getting this perceived optimal amount of sleep will likely lead to better health outcomes, including better heart and brain health.
Sources: Proceedings of the National Academy of Sciences, Science Daily
