A Robert Koch Institute study of 7,349 adults found that just 51.6% of Germans achieve the recommended nightly sleep duration, MDR Wissen reported. Falling short of these targets also raises the likelihood of dying earlier.
The survey, conducted via standardized computer-assisted telephone interviews between May 2023 and February 2024, found that adults aged 18 to 64 should sleep seven to nine hours per night, while those 65 and older should get seven to eight hours. Falling short raises the risk of high blood pressure, obesity and diabetes, while sleeping too long is associated with dementia and weight gain, according to the RKI findings cited by MDR Wissen. Both insufficient and excessive sleep are also linked to heart attacks and strokes. Researchers calculated average sleep duration from bedtime, sleep onset and wake time, but could not distinguish actual sleep from lying inactive rest.
Weekends vs. Weekdays Shape Sleep Patterns
Germans tend to catch up on sleep during weekends rather than weekdays. Only one-third of respondents go to bed before 10 p.m. on weekdays, a habit the RKI links to better adherence to sleep recommendations. Men sleep an average of 11 minutes longer than women, though women are more likely to fall within the recommended range.
Socioeconomic Status and Age Affect Sleep Duration
The study found that socioeconomically disadvantaged adults are more likely to sleep too little, while older adults tend to sleep longer than eight hours. Adults with higher formal education slept longer on average and met the recommendations more frequently. Those aged 65 and older were the least likely to meet sleep recommendations across the entire week.
Long Daytime Naps Carry Health Risks
Nearly half of respondents—45.3%—take a nap at least once a week. Of those, 25.5% nap for longer than 60 minutes. Naps under an hour reduce fatigue and improve performance, but longer naps are linked to metabolic disorders, cardiovascular disease, dementia and depression, according to the RKI. Women under 45 and men with higher education are most likely to exceed the 60-minute threshold. Napping once or twice a week was most common, followed by daily naps.
Researchers Call for Broader Sleep Monitoring
The RKI authors note that measuring sleep duration alone is insufficient for assessing sleep health. They recommend integrating continuous monitoring of sleep quality and sleep disorders into health monitoring to identify at-risk groups and target public health measures, the study concluded.
Tracking Sleep Deepens Self-Measurement Habits
Step counters on wrists, calorie apps on smartphones and now minute-by-minute monitoring of deep sleep phases in bed—the drive for self-optimization does not stop at our night’s rest.
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