People in Modern Societies Sleep More but Have Irregular Sleep Cycles

A new study challenges the common belief that modern industrialised life results in chronic sleep deprivation. Despite concerns about screen exposure and daily stress impacting sleep quality, findings suggest that individuals in industrialised societies actually sleep longer compared to those in less industrialised settings. Data from multiple studies indicate that sleep duration is higher among people in modern environments, contradicting widely held assumptions. However, while sleep quantity is greater, regular circadian rhythms appear to be more disrupted in these settings.

Study Findings on Sleep Patterns

According to research published in Proceedings of the Royal Society B, anthropologists David Ryan Samson and Leela McKinnon from the University of Toronto Mississauga conducted a meta-analysis of 54 global sleep studies. Their research examined the sleeping habits of 866 healthy adults, revealing that people in hunter-gatherer societies sleep fewer hours on average. Some groups recorded as little as 5.5 hours per night, while the general average in non-industrialised societies was 6.4 hours. In comparison, individuals in industrialised countries averaged over seven hours of sleep nightly.

Efficiency in Sleep and Circadian Rhythm Disruptions

Data also showed that sleep efficiency was higher in industrialised environments. It was reported that 88 percent of time spent in bed was used for sleep, whereas in less-industrialised settings, this figure was lower at 74 percent. Despite this, irregular circadian rhythms were more pronounced in industrialised societies. The circadian function index, which measures regularity in sleep-wake cycles, was recorded at 0.7 in non-industrialised societies but lower at 0.63 in industrialised settings.

Researchers attribute this difference to reduced exposure to natural light cues, which help regulate sleep cycles.

These findings suggest that sleep disturbances in modern environments may not stem from lack of sleep but rather from disrupted biological rhythms.