Adherence
Long-term population trends in Finland (1972-2005) show a statistically significant but small decrease in self-reported sleep duration (approx. 5.5 minutes per decade), primarily driven by a shift from 8-hour to 7-hour sleepers rather than an increase in extreme short sleepers.
Your sleep duration is likely stable around 7-8 hours regardless of how busy you are. The idea that you are 'losing' sleep rapidly is largely a myth; the shift is small and mostly involves people moving from 8 to 7 hours. Focus on maintaining 7-8 hours rather than trying to optimize for less.
The main results were that a minor decrease of self-reported sleep duration has taken place in Finland... the size of the reduction (about 4%) was relatively small, approximately 5.5 min per each 10 years... The proportion of 7 h sleepers has increased and, correspondingly, the proportion of 8 h sleepers has decreased, but the extreme ends of the sleep duration distribution remained unchanged.
Why this rating
Large sample size (251,083 individuals) and long time span (33 years), but relies on self-reported data which may underestimate actual sleep time.
Source
Trends in self‐reported sleep duration and insomnia‐related symptoms in Finland from 1972 to 2005: a comparative review and re‐analysis of Finnish population samples
Erkki Kronholm et al. · Journal of Sleep Research · 2008
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