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Rapamycin extends mouse lifespan 9–14%
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Blue-light glasses improve sleep quality
Walking 10 min after meals blunts glucose
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221 ‒ Understanding sleep and how to improve it — Whalespan

Content›Video›221 ‒ Understanding sleep an…

221 ‒ Understanding sleep and how to improve it

Peter Attia1h 37m · 2022-09-05

Support Rate

77%

109 of 142 claims supported

Support rate

109 of 142 claims supported

109 supported33 partial / not

Claims from this content

120

✓Well SupportedThe first half of the night features more deep non-REM sleep, while the second half features more light non-REM and REM sleep.✓Well SupportedA drop in core body temperature is necessary for falling asleep and staying deeply asleep.✓Well SupportedFlexibility in sleep schedules is beneficial for adolescents and teens due to their naturally later circadian rhythms.✕Not SupportedAfternoon caffeine consumption can negatively impact sleep by reducing deep non-REM sleep and making it harder to fall back asleep.✓Well SupportedMeditation practices of 1 minute, 3 minutes, 5 minutes, and 10 minutes all provide benefits, with many benefits starting to appear by 3 minutes.

More from Peter Attia

Peter Attia on Zone 2 Cardio

Peter Attia on Rapamycin (with Matt Kaeberlein)

Attia walks back the clinic protocol: too aggressive for healthy adults

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A. Volkovreader

4h

Bookmarking — the dossier-vs-overview split is the right call. Most of the time I want overview; sometimes I want receipts.

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Would love a "what would change this verdict" RSS feed. Sign me up if it exists.

✓Well SupportedIf unable to fall back asleep after approximately 25 minutes, get out of bed to avoid associating the bed with wakefulness.

✓Well SupportedIn hunter-gatherer societies, bedtime typically occurred two hours after sundown and waking occurred before dawn.

✓Well SupportedChronotypes, representing genetic predispositions to being morning or evening people, are roughly equally distributed among the population.

✓Well SupportedThe Morning Eveningness Questioner (MEQ) test can determine chronotype and correlates with genetic tests.

◐Partially SupportedSome individuals report that caffeine has no noticeable effect on their alertness or sleep.

✓Well SupportedFrom approximately 3 AM onwards, the brain shifts its sleep pattern, showing a greater appetite for REM sleep, especially in individuals who naturally sleep later.

✓Well SupportedSleeping in a room temperature of 65°F (18.3°C) leads to considerably better sleep on average compared to 75°F (23.9°C).

✓Well SupportedWarming the feet and hands promotes sleep by radiating heat from the body's core.

✓Well SupportedA natural sleep duration for healthy young adults is seven to nine hours per night.

✓Well SupportedOptimizing sleep hygiene, including a very dark and cold room, and maintaining consistent wake-up times are crucial for regulating sleep.

✓Well SupportedBoth caffeinated and decaffeinated coffee offer substantial benefits for general health, longevity, and cancer prevention.

✓Well SupportedBiphasic sleep in adults can involve one long sleep bout at night and a shorter bout during the day, timed to coincide with natural drops in alertness.

✓Well SupportedSleep spindles in stage two sleep are more frequent in the second half of the night, especially the last quarter.

✓Well SupportedStage 3 deep non-REM sleep has less than 50% deep slow brainwave activity, while stage 4 has more than 50%.

✓Well SupportedKeeping a phone outside the bedroom during sleep can improve sleep quality.

✓Well SupportedPeter Attia prioritizes an eight-hour sleep opportunity nightly to avoid early death and disease.

✓Well SupportedSleep efficiency, calculated as the percentage of time in bed spent asleep, is a key indicator of sleep quality.

✓Well SupportedCognitive Behavioral Therapy for Insomnia (CBT-I) is a non-drug approach that is as effective as sleeping pills and more effective long-term.

✓Well SupportedA wind-down routine should begin one hour before bedtime, involving turning off screens, going for a walk, meditating, breathwork, or reading a book.

✕Not SupportedIndividuals with insomnia should avoid naps as napping can be counterproductive for improving nighttime sleep.

✓Well SupportedWarming the paws of rats can cause them to fall asleep quicker and stay asleep, suggesting a link between peripheral temperature manipulation and sleep.

✓Well SupportedBeing very cold when getting into bed may increase sleep latency but lead to more uninterrupted sleep.

✓Well SupportedSleep is foundational for mental health, physical health, performance, immune function, wound healing, skin health, cognitive clarity, and longevity.

✓Well SupportedPeter Attia does not look at his phone for an hour after waking up.

✓Well SupportedRemoving clock faces from the bedroom can help poor sleepers with insomnia by reducing anxiety associated with knowing the time.

✓Well SupportedHumans are evolutionarily meant to spend approximately one-third of their lives sleeping, and this function is vital.

✓Well SupportedChronotype can shift towards later sleep and wake times during adolescence and then shift back earlier in older adulthood.

✓Well SupportedA colder room facilitates falling asleep more easily than a warmer room.

✓Well SupportedNon-REM sleep is divided into four stages, with stages 3 and 4 representing deep sleep, and stages 1 and 2 representing light non-REM sleep.

✓Well SupportedSleep spindles are coupled with slow waves and are critical for long-term memory transfer and strengthening brain cell connections.

◐Partially SupportedAlcohol abuse can lead to severe REM sleep deprivation, causing the brain to prioritize REM sleep by foregoing non-REM sleep.

◐Partially SupportedPeter Attia uses phosphatidylserine and Valium to manage jet lag during 12-hour time zone shifts.

✓Well SupportedIn narcolepsy, individuals may transition directly from wakefulness into REM sleep.

✓Well SupportedCognitive Behavioral Therapy for Insomnia (CBT-I) is considered the gold standard for treating insomnia.

✓Well SupportedNapping is beneficial if it does not impair nighttime sleep or cause grogginess.

✓Well SupportedREM sleep is characterized by rapid horizontal eye movements and is the principal stage for dreaming.

✕Not SupportedConsuming more than three to four cups of coffee per day may lead to negative health outcomes.

✓Well SupportedConsuming caffeine 8 to 10 hours before natural bedtime aligns with circadian biology and may optimize metabolism and cardiovascular health.

✓Well SupportedCognitive Behavioral Therapy for Insomnia (CBTi) is an effective non-pharmacological treatment for insomnia.

✕Not SupportedBringing a phone into the bedroom and opening it first thing in the morning leads to shallow sleep and waking up shortly before an alarm.

◐Partially SupportedOptimal sleep temperature may need to change throughout the night.

◐Partially SupportedFor insomnia treatment, sleep opportunity is often intentionally shortened to drive up sleep efficiency.

◐Partially SupportedPeter Attia previously averaged approximately 28 hours of sleep per week during his medical residency.

◐Partially SupportedOura Ring is helpful for distinguishing between time in bed and total sleep time.

◐Partially SupportedHuman physiology and circadian rhythms do not strongly suggest that the historical pattern of 'first sleep' and 'second sleep' was biologically mandated.

◐Partially SupportedThe health benefits associated with coffee may be primarily due to its antioxidant content rather than the caffeine.

◐Partially SupportedConstraining sleep opportunity forces the brain to prioritize sleep, thereby increasing efficiency.

◐Partially SupportedIn hotter seasons, individuals in equatorial hunter-gatherer tribes typically sleep less at night and compensate with short afternoon naps.

✓Well SupportedDuring deep sleep, the brain exhibits coordinated firing and silencing of hundreds of thousands of cortical neurons, creating large, powerful waves.

◐Partially SupportedSleep deprivation leads to quicker health reduction than food or exercise deprivation.

◐Partially SupportedSlow rolling eye movements are the first physiological sign of transitioning from wakefulness into sleep.

✕Not SupportedThe 'first sleep, second sleep' pattern is not biologically designed for humans.

◐Partially SupportedNaps can benefit learning, memory, immune function, heart rate variability, and blood pressure.

✕Not SupportedSleeping pills are associated with a higher risk of death, cancer, and susceptibility to infection.

✓Well SupportedWorking against one's chronotype can lead to disease and sickness.

◐Partially SupportedIndividuals with sleep onset or maintenance insomnia should avoid napping to maximize sleep pressure buildup.

✓Well SupportedSleep is a critical life support system protecting against nearly every major disease in the developed world.

◐Partially SupportedFocus on total sleep time and efficiency, not time in bed, when providing feedback to patients.

✓Well SupportedOptimizing sleep temperature can reduce total sleep need while still feeling rested.

◐Partially SupportedEngaging with social media, work emails, or similar content on electronic devices before bed is detrimental to sleep, regardless of light color.

✓Well SupportedModerated caffeine intake should be about three cups of coffee per day, with timing considered for individual sensitivity.

◐Partially SupportedSetting small, manageable goals for behavioral change increases the likelihood of success.

✓Well SupportedMaintaining a consistent sleep routine is important for adults to avoid negative sleep outcomes.

✓Well SupportedStimulants like caffeine and alcohol should be discontinued well before sleep as they disrupt mood and negatively affect sleep quality.

◐Partially SupportedSleep trackers typically do not measure qualitative aspects of sleep and may inaccurately represent the efficacy of changes based solely on quantity of sleep.

◐Partially SupportedIf a phone must be in the bedroom, use it only while standing for 5-10 minutes before putting it away to mitigate sleep procrastination.

✓Well SupportedTo achieve eight hours of actual sleep with 90% sleep efficiency, one needs to be in bed for approximately eight hours and 48 minutes.

✓Well SupportedShortening sleep to six hours can lead to losing up to 70% of REM sleep, disproportionately affecting the REM-rich phase of the night.

✓Well SupportedMorning caffeine consumption is acceptable due to potential health benefits, while evening caffeine use is not supported by data.

✓Well SupportedAn increase in ambient temperature late in the sleep cycle can help with waking up easier and feeling less groggy.

◐Partially SupportedPeter Attia's practice implements a sleep hygiene protocol relatively early for patients, especially those with sleep issues.

✕Not SupportedShort-term or infrequent use of benzodiazepines for sleep is not generally advocated for ongoing use.

◐Partially SupportedIf electronic devices were removed, most people would feel sleepy within 15-20 minutes, indicating their sleepiness was masked by the devices' activating effects.

◐Partially SupportedWhen awake with eyes closed, the brain exhibits an alpha rhythm at around 10 cycles per second.

◐Partially SupportedWhen awake with eyes open, the brain displays frenetic, high-frequency electrical activity with small amplitude due to asynchronous operation of different brain regions.

◐Partially SupportedWhen evaluating a CBT-I therapist, consider getting referrals, reviewing online feedback, and discussing their success rates and experience.

◐Partially SupportedA hot drink can raise core body temperature and contribute to feeling more awake.

◐Partially SupportedSleep science categorizes chronotypes into five groups: extreme morning, morning, middle, evening, and extreme evening.

◐Partially SupportedUnderstanding one's chronotype can explain struggles with energy levels and productivity.

◐Partially SupportedTechnology devices in the evening may mute sleepiness.

◐Partially SupportedHunter-gatherer studies suggest humans require an average of 7.5 to 9 hours of sleep, potentially in two chunks.

◐Partially SupportedEvolutionary programming suggests that spending a third of life sleeping indicates its critical importance.

◐Partially SupportedPeter Attia identifies five or six key 'levers' that individuals can adjust to improve sleep.

◐Partially SupportedGHB/Xyrem decreases sleep spindle activity, which is critical for learning, memory, and brain plasticity.

◐Partially SupportedTheta brain wave activity (6-7 cycles per second) is present in sleep stages one and two.

◐Partially SupportedConstraining total sleep time can increase brain efficiency and improve sleep.

◐Partially SupportedDaylight exposure during the first half of the day is important for sleep.

✕Not SupportedThe American College of Physicians recommended in 2016 that sleeping pills should not be the first-line treatment for insomnia due to health risks and nominal benefits over placebo.

✕Not SupportedPeter Attia advises against patients taking Ambien or Lunesta regularly, recommending them only as a safety net for occasional use.

✕Not SupportedXyrem is not a solution for optimizing sleep in individuals without narcolepsy due to cost and lack of deep sleep.

✕Not SupportedSedative-hypnotic sleeping pills should be used as a last resort due to their risks.

◐Partially SupportedA website from the American Academy of Sleep Medicine allows users to search for certified CBT-I therapists by zip code.

◐Partially SupportedSleep hygiene tips are ineffective for individuals with untreated sleep disorders such as insomnia or sleep apnea.

◐Partially SupportedDeep sleep involves long-distance information transfer in the brain, analogous to long-wave radio signals.

◐Partially SupportedCooler blues and shorter wavelength light are most detrimental to melatonin suppression.

◐Partially SupportedLow-to-moderate caffeine consumption is associated with a reduced risk of a range of diseases.

✕Not SupportedDiphenhydramine (Benadryl) should be avoided for sleep due to risks similar to sleeping pills.

◐Partially SupportedTaking between 3 to 18 sleeping pills per year was associated with a statistically significant increase in mortality risk.

◐Partially SupportedA hot bath or shower helps lower core body temperature by drawing blood to the skin's surface, facilitating heat radiation.

✕Not SupportedOver-the-counter sleep aids like Benadryl and Advil PM are not recommended for improving sleep.

◐Partially SupportedFor individuals with narcolepsy, medications like Xyrem may be a necessary 'lesser of two evils' despite potential negative impacts on sleep spindles.

✕Not SupportedGuinness World Records banned sleep deprivation attempts due to significant health risks including mental health issues, cancer, cardiovascular disease, metabolic syndrome, and suicide.

◐Partially SupportedStudies on light's effect on sleep have historically focused on melatonin suppression, potentially overlooking downstream consequences on sleep quality.

◐Partially SupportedUpon falling asleep, humans and all mammals experience two main stages: non-rapid eye movement (NREM) sleep and rapid eye movement (REM) sleep.

◐Partially SupportedFuture studies are needed to disambiguate whether light stimulation's impact on sleep is due to light wavelength or cognitive activation.

◐Partially SupportedSome animal studies suggest warmer color lights may have stronger blocking effects on melatonin than blue light.

◐Partially SupportedSetting manageable goals is a useful approach for behavioral change.

✕Not SupportedPeter Attia now emphasizes the activating and arousing nature of electronic devices as a more significant factor in sleep disruption than blue light.

◐Partially SupportedMedications that do not produce natural sleep should be considered a last resort for sleep difficulties.

◐Partially SupportedPeter Attia drinks decaffeinated coffee in the mornings.

◐Partially SupportedHuman sleep duration has decreased by approximately 20-25% over the past 70 years, a reduction comparable to a 20-25% decrease in oxygen saturation.

◐Partially SupportedInsomnia may sometimes be a mismatch between an individual's chronotype and their work schedule.

?Limited ResearchThe efficacy and safety of Tylenol PM for sleep are not sufficiently established.

◐Partially SupportedIn cooler, darker winter seasons, people tend to sleep longer at night and take fewer daytime naps.

◐Partially SupportedGHB/Xyrem appears to increase the amount of slow-wave sleep as scored by technicians because it induces slow brainwave activity, but its electrical signature does not resemble naturalistic sleep.