Sleep Without the Eight-Hour Rule: Your Ideal Snooze Is Personal
New research argues there is no universal eight-hour sleep rule: hunter-gatherer groups often sleep around 5.7–7.1 hours, and recent health studies suggest the optimal range is roughly 6.4–7.8 hours depending on the person and organ. Both too little and too much sleep are linked to health risks, but timing, regularity, and weekend catch-up also play roles. Modern patterns are delayed by artificial light, yet guidelines now acknowledge wide individual variation, typically recommending about 7–9 hours for many adults. The takeaway: sleep enough when you can, and don’t stress over an occasional bad night.