Mixed
Sleep durations outside the 7-8 hour range (short <6 hours or long >=9 hours) are associated with increased risks of cardiovascular disease, diabetes, depression, accidents, and mortality, with specific demographic and health factors driving these deviations.
Aim for 7 hours of sleep as a baseline, but recognize that this is not a rigid rule. If you are pregnant, have a chronic condition, or are under high stress, your body may need more or less sleep. Focus on sleep quality and consistency rather than hitting an arbitrary number. If you consistently struggle with sleep, look at external factors like work hours, stress, and health conditions before assuming it is a personal failing.
Sleep durations that are longer or shorter than 7–8 hours in a 24-hour period are associated with cardiovascular disease and diabetes risk factors (1–5), depression (6, 7), automobile and workplace accidents (8–11), learning and memory problems (12), and excess mortality (13–19).
Why this rating
Large, nationally representative sample (N=110,441), cross-sectional design limits causal inference, but strong statistical associations and adjustment for numerous confounders.
Source
Sleep Duration in the United States: A Cross-sectional Population-based Study
Patrick M. Krueger et al. · American Journal of Epidemiology · 2009
DOI 10.1093/aje/kwp023
Related findings · Mixed
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