How To Improve Your Sleep and Why You Should with Professor Matthew Walker #147
Professor Matthew Walker, a world-leading sleep researcher and author of 'Why We Sleep', discusses how sleep impacts physical and mental health. He offers actionable tips to improve sleep duration and quality, and addresses listener questions on topics like polyphasic sleep, caffeine, and sleep trackers.
Deep Dive Analysis
14 Topic Outline
Introduction to Sleep's Importance and Matthew Walker's Return
Why Sleep is the Single Most Effective Health Reset
Understanding Optimal Sleep Duration and Sleep Efficiency
Addressing Perceived Unrealistic Sleep Needs and Polyphasic Sleep
Strategies for Increasing Sleep Opportunity and Overcoming Time Constraints
Impact of COVID-19 on Sleep Duration, Timing, and Dreaming
REM Sleep as Emotional First Aid and Memory Processing
Effects of Caffeine and Alcohol on Sleep Quality
Matthew Walker's Evolving Stance on Caffeine Consumption
Effectiveness, Adherence, and Downsides of Sleep Trackers
Impact of Meal Timing and Temperature on Sleep Quality
The Intimate Connection Between Sleep Health and Immune Function
Practical Tips for Improving Sleep Hygiene and Daily Routines
Importance of Addressing Underlying Sleep Disorders
7 Key Concepts
Sleep Efficiency
This refers to the percentage of time you spend actually sleeping while in bed. A healthy sleep efficiency is typically between 85% and 95%, meaning that to achieve 7 hours of sleep, you often need to be in bed for at least 8 hours.
Sleep Opportunity
This is the total amount of time an individual allocates to be in bed for the purpose of sleeping. Providing sufficient sleep opportunity is crucial to allow the body and brain to achieve the necessary duration of actual sleep.
Cognitive Behavioral Therapy for Insomnia (CBTI)
An alternative to sleeping pills, CBTI is a non-pharmacological therapy that helps individuals regain confidence in their ability to sleep. It works by retraining the brain's association of the bed and bedroom with being asleep, rather than awake.
Chronotype
An individual's natural, genetically determined inclination to sleep and wake at a particular time, classifying them as either a 'morning type' (lark) or an 'evening type' (night owl). Society is often biased towards morning types, making it challenging for evening types to align with their natural rhythms.
REM Sleep (Dream Sleep)
Rapid Eye Movement sleep is a crucial stage where dreaming primarily occurs. It acts as 'emotional first aid,' processing difficult emotional experiences by stripping away the emotional charge from memories while preserving the informational content.
Memory Reconsolidation
This is the process where, each time a memory is recalled, it becomes temporarily unstable and open to modification. This allows for updating, re-contextualizing, or even dissipating the emotional tenor of past difficult or traumatic experiences.
Orthosomnia
A condition where individuals develop an unhealthy obsession or anxiety about achieving 'perfect' sleep metrics as reported by sleep trackers. This preoccupation can paradoxically worsen sleep quality and lead to increased stress about sleep.
9 Questions Answered
Adults generally need between 7 to 9 hours of sleep per night, but it's important to differentiate between actual sleep duration and 'sleep opportunity' (time in bed), as sleep efficiency means you need to be in bed longer to achieve your target sleep.
While brief awakenings are normal, prolonged periods of wakefulness (e.g., an hour) in bed are not beneficial and can teach your brain to associate the bed with being awake, making it harder to fall asleep later.
The pandemic has led to an increase in overall sleep duration for many, a shift to later bedtimes and wake-up times (favoring 'night owls'), and an increase in dreaming, including 'COVID dreams,' due to more REM sleep and a greater need for emotional processing.
REM sleep acts as 'emotional first aid,' processing difficult emotional experiences by stripping away the emotional charge from memories, allowing individuals to remember the event without reliving the same visceral reaction, thus providing overnight therapy.
Caffeine can make it harder to fall asleep, make sleep more fragile, and reduce the electrical quality of deep sleep; however, moderate doses consumed before 10 AM may offer health benefits, largely due to antioxidants in coffee rather than caffeine itself.
Alcohol is a sedative, not a sleep aid; it fragments sleep, makes it more fragile, and potently suppresses REM sleep, leading to a less restorative night and a 'rebound' of REM sleep during sobriety for heavy drinkers.
Many wearables (rings, wristwatches) are reasonably accurate (70-80% for total sleep, 40-70% for sleep stages) and can be great behavioral change tools, but for some, they can lead to 'orthosomnia' (anxiety about sleep metrics) and should be avoided if they cause distress.
Eating too close to bedtime can disrupt sleep quality, potentially due to the digestive tract's activity and the thermogenic effect of food, which raises core body temperature when it needs to drop for sleep.
Sleep is intimately linked to immune health; sufficient sleep restocks immune weaponry, sensitizes the body to immune factors, and individuals sleeping less than 7 hours are significantly more susceptible to infections like the common cold and pneumonia.
23 Actionable Insights
1. Prioritize 7-9 Hours Sleep
Aim for 7 to 9 hours of sleep per night, as scientific evidence shows that shorter sleep duration predicts a shorter lifespan and negatively impacts overall health and wellness.
2. Allow 8+ Hours In Bed
To achieve a minimum of 7 hours of actual sleep, allocate at least 8 hours and 13 minutes in bed, accounting for normal sleep efficiency (85-95% of time in bed spent asleep).
3. Consult Doctor for Sleep Issues
If you consistently struggle with sleep or suspect a sleep disorder like insomnia, sleep apnea, or heavy snoring, consult a doctor for diagnosis and treatment, as general tips may not be sufficient.
4. Try CBTI for Insomnia
For insomnia, explore Cognitive Behavioral Therapy for Insomnia (CBTI) as a highly effective, long-term alternative to sleeping pills, without the harmful side effects.
5. Incremental Sleep Gains
Start with small, incremental changes to improve sleep, such as going to bed 15 minutes earlier or waking up 5 minutes later, as even 15-20 extra minutes per day can significantly boost health over time.
6. Create Wind-Down Routine
Develop a consistent wind-down routine before bed (e.g., bath, reading, light stretching, meditation) to gradually prepare your brain and body for sleep, as sleep is a gradual physiological process, not a light switch.
7. Set Bedtime Alarm
Set a ’to bed’ alarm to remind yourself to start your wind-down routine, aiming for an 8-hour sleep opportunity, as this persistent notification can help you get to bed earlier.
8. Pre-Bed Prep Hour
An hour before your planned bedtime, complete all pre-sleep tasks like changing into pajamas, brushing teeth, and washing your face, to streamline the process and add 15-20 minutes to your sleep opportunity.
9. Leave Bed If Awake
If you’re awake in bed for more than 25 minutes (trying to fall asleep or get back to sleep), get out of bed, go to another room, and engage in a relaxing activity in dim light (e.g., stretching, meditation, reading) until you feel sleepy, then return to bed.
10. Avoid Evening Alcohol
Refrain from consuming alcohol in the evening, as it fragments sleep, makes it more fragile, and potently suppresses REM sleep, which is vital for emotional processing and memory.
11. Manage Caffeine Wisely
Be mindful of caffeine’s long half-life (5-6 hours) and quarter-life (10-12 hours); cut off caffeine intake by late morning or noon to prevent it from disrupting your sleep quality at night, even if you don’t feel its effects.
12. Decaf for Antioxidants
If caffeine negatively impacts your sleep, consider drinking decaffeinated coffee, as many of coffee’s health benefits come from its rich antioxidant content, not the caffeine itself.
13. Stop Eating Before Bed
Cease all eating, including snacking, two to three hours before bedtime, as consuming food too close to sleep can negatively affect sleep quality, heart rate, and recovery.
14. Choose Healthy Bedtime Snack
If you must have a snack before bed, opt for a high-fiber, high-protein option instead of high-sugar foods, as sugar is thermogenic and can raise core body temperature, disrupting sleep.
15. Optimal Bedroom Temperature
Set your bedroom temperature to approximately 18-18.5 degrees Celsius (65-66 degrees Fahrenheit), as a slight drop in core body temperature is necessary to fall and stay asleep.
16. Ensure Bedroom Darkness
Maintain regularity in your sleep schedule, ensure your bedroom is dark, turn off screens, and dim half the lights in your house before bed to signal to your body it’s time to sleep.
17. Remove Bedroom Clocks
Remove all visible clocks from your bedroom if you struggle with sleep, as checking the time during awakenings can increase anxiety and worsen insomnia.
18. Don’t Count Sheep
Do not attempt to count sheep to fall asleep, as studies have shown this technique can actually worsen sleep.
19. Visualize to Aid Sleep
If anxious thoughts prevent sleep, try a visualization technique: mentally ‘walk’ through a pleasant, familiar scene (e.g., a walk in the woods or on the beach) for 5-10 minutes to distract your mind.
20. No Tech In Bedroom
Strive to keep technology, especially phones, out of the bedroom entirely. If this is too difficult, try to delay touching your phone in the morning until after you’ve completed initial routines.
21. Use Phone Standing Only
If you absolutely must bring your phone into the bedroom, enforce a rule to only use it while standing up; this discourages prolonged use and prompts you to put it away when you want to relax for sleep.
22. Avoid Sleep Tracker Anxiety
If using a sleep tracker causes anxiety or ‘orthosomnia’ (worry about getting sleep right), stop using it, as the increased anxiety will likely worsen your sleep rather than improve it.
23. REM Sleep Processes Difficult Emotions
Recognize that REM sleep acts as ’emotional first aid’ or ‘overnight therapy,’ processing difficult experiences and reducing their emotional charge, which can help you feel better the next day.
7 Key Quotes
The shorter your sleep, the shorter your life. Short sleep predicts all-cause mortality.
Matthew Walker
Sleep is the single most effective thing that you can do to reset your brain and body health each and every day.
Matthew Walker
Less sleep does not equal more productivity.
Matthew Walker
It's not time that heals all wounds, it's time during sleep and specifically dream sleep that provides that form of emotional convalescence.
Matthew Walker
The best bridge between despair and hope is a good night of sleep.
E. Joseph Cossman
Sedation is not sleep, but we mistake that.
Matthew Walker
What gets measured gets managed.
Matthew Walker
3 Protocols
Managing Prolonged Wakefulness in Bed
Matthew Walker- If you've been awake for longer than 25 minutes while trying to fall asleep or get back to sleep, get up and get out of bed.
- Go to a different room and, in dim light, do some gentle stretching, meditation, or reading.
- Avoid checking your phone or eating, as these can become triggers for waking up.
- Only return to bed when you feel sleepy again, with no time limit for how long you stay out of bed.
Increasing Sleep Opportunity
Matthew Walker- Set a 'to bed' alarm that signals when to start preparing for sleep, aiming for an 8-hour sleep opportunity.
- At least an hour before your planned bedtime, get changed into your bed clothes, brush your teeth, floss, and complete all other usual pre-bed routines.
General Sleep Hygiene Tips
Matthew Walker- Maintain regularity by going to bed and waking up at consistent times, even on weekends.
- Ensure darkness in your sleep environment by dimming half the lights in your house and turning off screens an hour before bed.
- Set your bedroom temperature to an optimal 18-18.5 degrees Celsius.
- Avoid lying in bed awake for prolonged periods; if struggling, follow the 'Managing Prolonged Wakefulness' protocol.
- Avoid alcohol and caffeine, especially later in the day.
- Establish a consistent wind-down routine before bed, such as a bath, reading, light stretching, or meditation.
- Remove all clock faces from your bedroom to prevent anxiety about time.
- If struggling to sleep, visualize a calming walk in detail (e.g., in the woods or on a beach) to distract your mind.
- Keep technology out of your bedroom; if you must bring your phone in, only use it while standing up, and put it away if you need to sit down.