Sleep Science Articles
In-depth guides to sleep cycles, circadian biology, chronotype, caffeine, melatonin, and the real science behind common sleep questions. Each article is grounded in peer-reviewed research with citations.
Sleep Timing
3 guidesSleep TimingSleep Cycles ExplainedWhat happens during a 90-minute sleep cycle, why each stage matters, and how to wake up without feeling wrecked.Sleep TimingCaffeine and Sleep: Half-Life, Adenosine, and Your Cutoff TimeHow caffeine works in the brain, why its half-life matters more than how you feel, and the research on its real impact on sleep architecture.Sleep TimingWhy 90-Minute Cycles MatterSleep cycles are 90 minutes for a reason. The research behind the cycle, why timing wake-ups to cycle ends reduces sleep inertia, and how individual cycle length varies from 80 to 110 minutes.
Circadian
5 guidesCircadianMelatonin for Sleep: What the Research Actually SaysUnderstand how melatonin works, optimal dosing (0.5mg vs 10mg), timing, and when it actually helps versus when it doesn't.CircadianWhat Is a Chronotype? Lion, Bear, Wolf & Dolphin ExplainedUnderstand your natural sleep-wake rhythm, the genetic basis of chronotype, social jet lag, and how your type affects health and performance.CircadianDelayed Sleep Phase Syndrome: When Night Owl Becomes ClinicalDSPS diagnosis, prevalence, treatment options including light therapy, melatonin timing, and chronotherapy for persistent late sleep timing.CircadianSocial Jet Lag: Why Monday Feels Like a Time Zone AwayWhat social jet lag is, how it is measured from mid-sleep timing, the research linking it to weight and mood, and how to shrink the gap between your body clock and your schedule.CircadianScreens and Sleep: What Blue Light Really Does at NightHow evening screen light suppresses melatonin and delays your body clock, whether night filters help, and how to set a screen cutoff that fits you.
Sleep Health
5 guidesSleep HealthAlcohol and Sleep: The Science Behind 'I Sleep Better After a Drink'Why alcohol makes you drowsy but worsens sleep quality, REM suppression, sleep architecture damage, and the second-half rebound effect.Sleep HealthHow to Recover from Sleep Debt: A Science-Based PlanSleep debt is real and it accumulates. How long recovery actually takes, what strategies work, and why the weekend catch-up is mostly a myth.Sleep HealthSleep Needs by Age: NSF Guidelines for Every Life StageHow much sleep each age group actually needs, from newborns to older adults, why needs change across life, and what really counts as enough.Sleep HealthWhat Is Sleep Hygiene? The Habits That Set Up Good SleepThe everyday habits and conditions that make good sleep more likely, which ones have the strongest evidence, and where hygiene helps versus where it is not enough.Sleep HealthBedroom Temperature and Sleep: Why Cool WinsWhy a cool bedroom helps you fall asleep, the core body temperature drop behind it, the research-backed 60 to 67°F range, and how bedding and age change your ideal number.
Life Situations
12 guidesLife SituationsTeen Sleep Deprivation: Why Your Teenager Is Always TiredThe biological sleep shift in puberty, brain development impacts of chronic short sleep, school start times, and strategies to protect teenage sleep.Life SituationsJet Lag From New York to London, Paris and AmsterdamWhy a 5 hour eastward shift on an overnight flight hurts more than its zone count, the prep-night and arrival plan for both directions, and when a short trip is not worth adapting to.Life SituationsJet Lag From Los Angeles to Tokyo, Seoul, Shanghai and Hong KongWhy the trans-Pacific trip is a 7 to 9 hour delay going out and an advance coming home, so the return is the harder leg, with the day-by-day plan for both directions.Life SituationsJet Lag From New York to Dubai, Doha and DelhiThe largest eastward advance from the East Coast, 8 to 10.5 hours on an overnight flight, why prep nights pay most on this route, and the day-by-day plan for both directions.Life SituationsJet Lag Flying From the US West Coast to India (and Back)A near-inverted 10.5 to 11.5 hour shift: why the calculator delays your clock going out, why the return is the hardest leg of any US route, and the plan for both directions.Life SituationsJet Lag From Los Angeles to Sydney and AucklandWhy the date line costs a day but not your body clock: a 5 to 7 hour delay out (3 for Auckland in the US winter), the harder advance home, and the plan for both directions across the seasons.Life SituationsShift Work Sleep Guide: How to Sleep Better on Night ShiftsWhat actually works for shift workers: light management, strategic napping, rotating schedule advice, and building a sustainable sleep routine.Life Situations4 on 4 off Sleep Schedule: Sleeping on a Rotating 12-Hour PatternA practical plan for 4 on 4 off: holding one sleep window through four 12-hour nights, the switch day after your last night, and using the four days off well.Life SituationsPanama Schedule (2-2-3) Sleep GuideWhy two-night blocks are too short to adapt to, the anchor sleep strategy that keeps your clock day-oriented, and how to use the every-other-weekend break.Life SituationsDuPont Schedule Sleep GuideHandling the DuPont rotation's four-night block, the quick turnarounds between shift types, and the seven-day break that settles the month's sleep debt.Life SituationsSleep Banking Guide: How to Prepare for Unavoidable Sleep LossThe science of sleep banking, how much sleep credit you can accumulate, and effective strategies for preparing for scheduled sleep loss.Life SituationsWake Windows by AgeAge-by-age wake windows from newborn through preschool, with the science behind why they matter, sleepy cues that signal a closing window, and the two-nap to one-nap transition.
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