Why We Sleep
Why We Sleep: The New Science of Sleep and Drams by Matthew Walker
🚀 The Book in 3 Sentences
Sleep is universal. There is a deep biological root to suggest it is vital for us. We have evolved needing sleep.
There is little targeting or information about sleep but lots on diet and exercise. Despite sleep being a fundamental and a key pillar for diet and exercise.
There is lots of studies and research on how sleep affects cognitive and physical performance in both the short and long term. The book explains how neglecting sleep undercuts your creativity, problem solving, decision-making, learning, memory, heart health, brain health, mental health, emotional well-being, immune system, and even your life span.
🎨 Impressions
This is a comprehensive in-depth insight into the world of sleep. There are lots of scientific studies and research that are used to explore the importance of sleep.
How I Discovered It
Sleep, and better sleep, seemed like a fundamental concept, that I knew very little about. I am in general fascinated by dreams as well as how we spend 1/3 of our life – I thought I would delve in and explore more about it.
Who Should Read It?
If you currently don't think sleep is important, or view it as a waste of time, I seriously recommend you read this book as I guarantee it will change your mind for the better. If you find yourself reaching for caffeine or with low energy levels, or interested in dreams and their impact on memory and creativity, then this book is a great starting point.
☘️ Matthew Walker's Top 12 Tips for Better Sleep
Stick to a sleep schedule – go to bed and wake up at the same time each day
Exercise is great but not too late in the day. 30 mins most days but not before 2-3 hours before bed.
Avoid caffeine and nicotine. It can take 8 hours to wear off.
Avoid alcohol before bed - it robs us of REM sleep
Avoid large meals and beverages late at night – large meals cause indigestions, too much drink can cause waking up in the night
Avoid medicines that delay or disrupt sleep –
Don’t take naps after 3pm – naps help but too late can mean you struggle to fall asleep at night
Relax before bed – take time to unwind so don’t overschedule late at night
Take a hot bath before bed – the drop in body temperature after may help feel sleepy
Dark, cool gadget-free bedroom, these distract us from sleep
Daylight is key to regulate daily sleep patterns wake up with the sun, take 30 mins outside daily
Don’t lie in bed awake – do a relaxing activity until you feel sleepy
✍️ My Top 3 Quotes
Before Edison, and before gas and oil lamps, the setting sun would take with it this full stream of daylight from our eyes, sensed by the twenty-four-hour clock within the brain.
Universal parental wisdom knows that bad sleep the night before leads to a bad mood and emotional reactivity the next day.
Sleep is the single most effective thing we can do to reset our brain and body health each day.
📒 Summary + Notes
A commonly asked question: Does everyone really need seven or eight hours of sleep a night? The answer is 100% yes, even if you’ve convinced yourself otherwise. The number of people who can survive on five hours of sleep or less without impairment, when rounded to a whole number, is zero.
2 Driving Forces of Sleep:
Circadian Rhythm
This is a day-night rhythm that makes you tired or alert depending on time of day
It is internally formed, but affected by exposure to light, activity, and meals
Melatonin is generated in darkness
Sleep Pressure (Adenosine)
There is a chemical called adenosine that builds up throughout the day. This is what causes us to be sleepier the longer you stay awake
Caffeine blocks adenosine receptors in the brain, but it still produces adenosine so caffeine just temporarily reduces this tiredness feeling
Adenosine levels can only be lowered by sleeping
Stages of Sleep:
NREM occurs earlier in the sleep phase, while REM is concentrated later.
Non-REM sleep: This relates to the storing and strengthening of the raw ingredients of new facts and skills. It is is responsible for pruning memories, transferring short-term memory to long-term memory, gaining “muscle memory,” growth hormone secretion, and parasympathetic nervous system activation.
REM sleep: This causes the interconnecting of these raw ingredients with each other, with all past experiences, and building an evermore accurate model of how the world works. It is responsible for forming new neural connections, problem-solving, dreaming, blunting emotional responses to painful memories, reading other people’s facial emotions, and neonatal synaptogenesis.
Why Sleep:
Sleep deprivation shows consistently bad outcomes. Nothing is reported to be beneficial from sleep deprivation - it is only good for us.
Sleep deprivation is associated with: higher mortality, risk of cancer, heart disease, weight gain, rate of infection, irritability, inflammation.
Sleep deprivation lowers performance: lower productivity, social fluidity, rational decision-making, memory recall, emotional control, testosterone, immune system function, response to flu vaccine.
In the extreme, chronic sleep deprivation causes death.
If you think you are gaining time by sleeping less, it will actually result in lower productivity and creativity.
Many studies on millions of people show that the shorter your sleep, the shorter your life
Insufficient sleep proves ruinous to all major physiological systems of the human body: Cardiovascular; Metabolic; Immune; Reproductive.
Short sleep is a proven recipe for weight gain, and will: Increase hunger and appetite; compromise impulse control within the brain; increase food consumption(especially high calorie foods); decrease feels of food satisfaction after eating; prevent effective weight loss when dieting
Less sleep results in lower sperm count, testosterone, and libido
Women who suffer from lower quality and less sleep are more likely to have irregular menstrual cycles and lower fertility
Physical attractiveness is decreased by lack of sleep. “Beauty sleep” is real
Benefits of Dreaming:
One function of REM sleep is that is acts as therapy for emotionally traumatic events. It reduce the emotional response to them. This is why the next day yesterdays issue doesn't seem so dramatic.
REM sleep increases our ability to accurately assess and decode other people’s emotions and intent through facial expressions
It helps to re-calibrate ourselves, and reset.
REM sleep and the act of dreaming is inspires creativity and promotes problem solving and intelligent information processing.
Improving Understanding and Awareness of the Importance of Sleep
Sleep education: There is currently no class on rest or sleep despite there being many about physical activities. Developing a simple educational module in schools will result in us raising our children with good sleep habits.
Flexible working hours: This will mean night owls, who genetically and naturally sleep and wake later, can also work later and get the benefits of a full night rest. Working hours can be tailored to the individual.
Public campaigns: There are educational campaigns about cancer, HIV and drugs, but there aren’t such for better sleep. Given the significant consequences of insufficient sleep it seems like it would be a wise way to spend some of the healthcare budget.
Summary Points:
Within the space of a mere hundred years, human beings have abandoned their biologically mandate need for adequate sleep – one evolution spent 3,400,000 years perfecting in service of life support functions.
As a result of the decimation of sleep throughout industrialised nations is having a catastrophic impact on our health, life expectancy, safety, productivity and education of children.
The silent sleep loss epidemic is the greatest public health challenge we face in the 21st century. If we wish to avoid the suffocating noose of sleep neglect, the premature death it inflicts, the sickening health it invites, a radical shift in our personal, cultural, professional and social appreciation of sleep must occur.
It is time for us to reclaim our right to a full night sleep, without embarrassment or the damaging stigma of laziness. In doing so we can be reunited with that powerful elixir of wellness, volatility, dispensed through every conceivable biological pathway. Then we may remember what it feels like to be truly awake during the day infused with the deepest plenitude of being.
