Benefits Backed by Science
Stronger Defences
Sleep boosts immunity. Under 6 hours quadruples your risk of catching a cold.
Better Memory
Sleep locks in learning. Post-study sleep improves memory recall by 20–40%.
Safer Days
Rest helps keep you safe. Missing even 1–2 hours raises the risk of an accident.
Emotional Stability
Poor sleep fuels stress. One all-nighter increases emotional reactivity by around 60%.
Sleep Smarter
With over 1 million nightly active users, Sleep Cycle combines science and technology to help you get the sleep you need to perform at your best.
Sleep for Longevity
Eight Hours Adds Years
Getting enough good-quality sleep is one of the simplest ways to support a longer, healthier life. Consistent, restorative sleep helps regulate blood pressure, metabolism, and immune function, lowering the risk of age-related illnesses.
The Sweet Spot
Adults who regularly sleep 7–8 hours can live longer than those who sleep too little or too much.
Keep it Consistent
Irregular sleep schedules can increase the chance of health risks compared to a consistent routine.
Do Not Disturb
Continuous sleep supports longevity, while broken sleep is linked to a shorter health span of older adults.
Tired Can Equal Tipsy
Sleep debt builds up fast. Two weeks of getting just 6 hours a night has the same effects on your brain as not sleeping 1–2 days straight. You might not notice the difference, but tests show worse focus, memory and decision making.
After 24 hours awake, your reaction time can be the same as someone with blood alcohol above the legal driving limit.
Learn More Efficiently
Sleep on It
Sleeping after learning can improve your memory by 20–40%, while cramming all night and not sleeping leads to forgetfulness. Even short naps can boost memory in the afternoon.
Boost Your Energy
More sleep means more motivation. Just two nights of short sleep makes tasks feel harder and lowers energy by 12–15%.
Sleep research about health and well-being
In a viral exposure study, people sleeping less than 5 hours had 4.5 times greater risk of developing a cold, while those sleeping 5-6 hours had 4.24 times greater risk compared to those sleeping more than 7 hours per night Behaviorally Assessed Sleep and Susceptibility to the Common Cold – PMC. Studies have found that insufficient sleep makes it more likely to catch the common cold or flu in people who sleep less than six or seven hours per night Sleep & Immunity: Can a Lack of Sleep Make You Sick? | Sleep Foundation.
Key study: Prather et al. (2015) – Behaviorally Assessed Sleep and Susceptibility to the Common Cold
Lack of sleep can cut learning ability by up to 40%, and sleep before learning helps prepare the brain for memory formation NIH News in HealthSleep Foundation. Studies using targeted memory reactivation during sleep showed memory benefits ranging from 13% to 53%, with patients showing an average 36% improvement for cued versus uncued memories Electrophysiological markers of memory consolidation in the human brain when memories are reactivated during sleep – PMC. Napping has been shown to enhance performance on perceptual learning tasks, with naps significantly improving discrimination thresholds The impact of frequent napping and nap practice on sleep-dependent memory in humans | Scientific Reports.
Key studies:
NIH research showing sleep improves memory consolidation
Sleep significantly enhanced consolidation of factual knowledge (effect size = 0.72) Sleep after learning aids the consolidation of factual knowledge, but not relearning
The AAA Foundation found that drivers missing 2-3 hours of sleep in a 24-hour period more than quadrupled their crash risk compared to drivers getting seven hours Missing 1-2 Hours of Sleep Doubles Crash Risk | AAA Newsroom. Drivers who slept 1 or more hours less than their usual amount had significantly elevated crash rates, with those sleeping 4+ hours less than usual having 10.2 times the crash rate Acute Sleep Deprivation and Risk of Motor Vehicle Crash Involvement – AAA Foundation for Traffic Safety. Sleep-deprived employees are 70% more likely to be involved in workplace accidents than well-rested colleagues The Relationship Between Sleep and Workplace Accidents | Sleep Foundation.
Key study: AAA Foundation – “Acute Sleep Deprivation and Risk of Motor Vehicle Crash Involvement”
One night of sleep deprivation triggers a 60% amplification in reactivity of the amygdala in response to emotionally negative pictures, with reduced connectivity to prefrontal regions that regulate emotion The Role of Sleep in Emotional Brain Function – PMC. Meta-analysis of 64 studies found sleep loss resulted in a moderate positive effect on negative mood (effect size = 0.45) and a large negative effect on positive mood (effect size = -0.94) The effect of sleep deprivation and restriction on mood, emotion, and emotion regulation: three meta-analyses in one – PMC. University of Pennsylvania researchers found that subjects limited to 4.5 hours of sleep for one week reported feeling more stressed, angry, sad, and mentally exhausted Sleep and Mood | Sleep Medicine.
Key study: Yoo et al. (2007) – fMRI study showing 60% increase in amygdala reactivity after sleep deprivation
Meta-analysis of 16 prospective studies with 1.3 million participants found short sleep duration (less than 6 hours) was associated with 12% greater risk of death, while both short and long sleep showed associations with adverse health outcomes including metabolic, endocrine, and immune pathway changes Sleep Duration and All-Cause Mortality: A Systematic Review and Meta-Analysis of Prospective Studies – PMC. People with all five favorable sleep behaviors were 30% less likely to die for any reason, 21% less likely to die from cardiovascular disease, and 19% less likely to die from cancer Getting Good Sleep Could Add Years to Your Life – American College of Cardiology. Sleep deprivation leads to rises in blood pressure, increased insulin resistance and diabetes risk, accumulation of belly fat, and prevents the brain from flushing away toxic byproducts Sleep and longevity: How quality sleep impacts your life span – Mayo Clinic Press.
Key studies:
Multiple large meta-analyses showing optimal sleep duration of 7-9 hours associated with lowest mortality risk
Sleep regularity is a stronger predictor of mortality risk than sleep duration
Being awake for 17 hours is similar to having a BAC of 0.05%, while being awake for 24 hours is similar to having a BAC of 0.10% (above the U.S. legal driving limit of 0.08%) CDCPubMed Central. After 17-19 hours without sleep, performance on some tests was equivalent or worse than at a BAC of 0.05%, with response speeds up to 50% slower Moderate sleep deprivation produces impairments in cognitive and motor performance equivalent to legally prescribed levels of alcohol intoxication – PMC. Two weeks of restriction to 6 hours time in bed per night resulted in cognitive deficits equivalent to those found after one night of total sleep deprivation PubMed CentralPubMed.
Key study: Williamson & Feyer (2000) – “Moderate sleep deprivation produces impairments in cognitive and motor performance equivalent to legally prescribed levels of alcohol intoxication”
More sleep means more motivation. Two nights of sleep deprivation significantly decreased motivation (effect size η² = 0.25) and vigor (effect size η² = 0.29), while significantly increasing feelings of fatigue (effect size η² = 0.21) Effects of two nights of sleep deprivation on executive function and central and peripheral fatigue during maximal voluntary contraction lasting 60s – ScienceDirect. Sleep restriction (three consecutive nights with 3-hour sleep opportunities) reduced the willingness to exert cognitive effort in healthy young adults compared to when fully rested Sleep Restriction Reduces Cognitive but Not Physical Motivation – PMC. Sleep-deprived participants perceived increases in work load and reduced their walking pace, and sleep deprivation resulted in reductions in the speed of task completion, work rates, and the number of solutions attempted The effects of sleep loss on capacity and effort – PMC. When sleep-deprived, cognitive performance is experienced as more effortful, and intrinsic motivation to perform dwindles Sleep deprivation, effort allocation and performance – ScienceDirect. Despite participants trying to compensate with increased exertion, they still experienced decreases in both subjective and objective performance as well as decreased positive affect Mild to moderate partial sleep deprivation is associated with increased impulsivity and decreased positive affect in young adults | SLEEP | Oxford Academic. Conversely, sleep extension showed marked improvements in vigor and significant decreases in fatigue (P < 0.01) PubMed CentralScienceDirect.Key studies:Azad et al. (2020) - "Effects of two nights of sleep deprivation on executive function and central and peripheral fatigue"Jurgelis et al. (2022) - "Sleep restriction reduces cognitive but not physical motivation"Engle-Friedman (2014) - "The effects of sleep loss on capacity and effort"