Why DO we sleep? The answer is bigger than you think
At Drowsy, our ardor for the enigmatic realm of sleep knows no bounds – that much is evident. Therefore, encountering the insights of neuroscientist and sleep authority Matthew Walker in his seminal work 'Why We Sleep' filled us with anticipation. This meticulously crafted piece delves deep into the fundamentals and perks of sleep, drawing from a wealth of research, biological intricacies, and evolutionary wisdom to shed light on the profound significance of rest.
Spoiler alert: It is a key indicator of health and longevity, and Walker starts with a clear message of sleep less, live less. But it’s not all dire – there are plenty of insights and takeaways that’ll help us get the most out of life, with healthy sleep. Here’s a summary:
Why: small question, big answer
Walker initiates the discourse with a somber portrayal of the perils of insufficient sleep on our health. Yet, he swiftly transitions to depict sleep as the "Swiss army knife of health," encapsulating its multifarious benefits succinctly. Let's embark on a scientific expedition into the realm of sleep.
Rejuvenation Mode: Walker underscores sleep as the ultimate catalyst for resetting our brain and body health daily. It is during this restorative phase that recovery and regeneration unfold, constituting an indispensable component of our overall well-being.
Harmony with Circadian Rhythms: Our bodies dance to the tune of a natural cycle, orchestrated by the circadian rhythm and governed by melatonin. Light signals wakefulness, while darkness cues sleepiness. This rhythm harmonizes with adenosine, a chemical that amplifies our urge to sleep throughout the day. As night falls, our inclination for wakefulness dwindles, while our "sleep drive" peaks—a symphony of biological cues urging us towards slumber.
The Symphony of Sleep Phases: Human sleep embraces an intricate interplay of REM (Rapid Eye Movement) and Non-REM stages. Non-REM sleep fosters memory consolidation and tissue repair, while REM sleep nurtures emotional equilibrium and creativity. Moreover, REM sleep serves as the canvas for dreaming—a poignant mechanism for processing stress, heightening emotional acumen, and unlocking solutions to perplexing problems.
The Toll of Sleep Deprivation: Against this backdrop of sleep's pivotal role, sleep deprivation—or accruing a sleep deficit—emerges as a stark counterforce to its benefits. Attention wanes, emotional reactivity surges, and the specter of cognitive ailments like Alzheimer’s looms larger. Physically, the ramifications are equally profound, elevating the risk of cardiovascular maladies and diabetes, while dampening fertility and athletic prowess.
What can we do to get good sleep?
Sleep, an intricate domain, is subject to a myriad of influences across our lifespan. From the demands of parenthood to the disruptions of travel, environmental clamor, and the flux of hormones during menopause – the variables are extensive. However, amidst this complexity, there remains agency over certain determinants that wield significant sway.
Illuminate judiciously. Exposure to artificial light at night, predominantly from screens, poses a threat to our natural sleep rhythms and compromises sleep quality. Of particular concern is blue light, which suppresses melatonin production at a rate twice that of warmer light sources.
Pinpointing the Ideal Thermal Environment. Our bodies intricately respond to temperature changes throughout the day, using them as cues for the sleep-wake cycle – cooler temperatures signify the approach of nighttime and promote sleep initiation. Emulating the natural temperature variations of the outdoors while indoors fosters a resilient circadian rhythm, thereby optimizing sleep quality.
Manage your consumption of caffeine and alcohol. Caffeine can disrupt your sleep by inhibiting adenosine receptors, masking your body's natural urge to rest. Similarly, while alcohol may induce drowsiness, it interferes with the quality of sleep, causing disruptions in your sleep cycle and hindering the essential REM sleep phase.
Adopt a balanced diet. Consuming excessive carbohydrates in the evening has been linked to reduced Non-REM sleep and an increased tendency to wake up during the night.
Follow a consistent schedule. Walker explains that the circadian rhythm evolved to align us with the earth's 24-hour cycle. Sunlight, being the most consistent cue, plays a pivotal role in regulating our body's rhythm and promoting a steady sleep pattern.
Acknowledge your innate rhythm. Walker highlights the evolutionary significance of individuals favoring either late-night activities (night owls) or early morning starts (morning larks). This adaptation likely emerged to reduce the group's exposure to nocturnal predators, as a mixed sleep pattern ensured minimal vulnerability during shared sleep periods.
