There´s no way getting around it: sleep is absolutely crucial for a vast array of bodily functions. Indeed, as maintained by sleep scientist Matt Walker, sleep is your superpower. The most important functions of sleep are: storage and consolidation of long-term memories, muscle recovery, strengthening of the immune system, increased attention, prevention of cardiovascular disease, among many other benefits. The benefits of adequate sleep will be expanded on in the body of this essay, including an explanation and the respective benefits of the different types of sleep.
Sleep has a measurable impact on different systems of the body: nervous system, cardiovascular system, reproductive system, immune system. Overall, according to Walker, short sleep predicts all-cause mortality.
The different stages of sleep have different functions and beneftis. Non-rapid eye movement sleep (NREM) has four different sub-stages, which progressively lead to deeper sleep. It is in the more advanced stages of NREM sleep that the immune system is boosted and rebalanced, together with the cardiovascular system. Furthermore, memory consolidation and the strengthening of neural connections also occurs during NREM sleep. On the other hand, rapid eye movement sleep (REM) is associated with an increase in creativity and emotional balance.
With regards to the immune system, inadequate sleep (e.g., 4 hours), leads to a 70% drop in natural killer cell activity, which are “immune assassins”. This increases the risk of development of prostate cancer, breast cancer and colon cancer. Sleep is so important that the world health organization has recently classified night-time shift work as a probable carcinogen.
With regard to the cardiovascular system, lack of sleep increases the risk of heart attacks and cardiovascular disease. For example, scientists limited a group of healthy adults to 6 hours of sleep a night for one week. After this, they measured the change in their gene activity profile compared to when these same adults were getting 8 hours of sleep a night. Their findings were astonishing: there was a decrease in the expression of genes related to immune function; contrastingly, there was an increase in the expression of genes associated with the promotion of tumours, inflammation and cardiovascular disease.
When it comes to sleep optimization, as maintained by neuroscience professor Dr. Huberman at Stanford Medical School, the single most important factor which contributes to greater sleep quality and duration is to view, ideally sunlight, for 2-10 minutes every morning after waking up. Bright light exposure (even on a cloudy day) soon after waking up stimulates a healthy spike of cortisol, which promotes wakefulness and focus throughout the day. More importantly, it is a foundational power tool to ensure high-quality and durable sleep: it has an immensely positive impact on your ability to fall and stay asleep later that night. The mechanism behind this effect is that exposure to light early in the day suppresses melatonin production (the “sleepiness” hormone”) and increases its secretion at night.
Other tips for better sleep are: a regular sleep-wake schedule, keeping the room in which you sleep cool, engaging in physical exercise, having a wind-down routine, avoiding the consumption of alcohol and also of caffeine after 4 pm. It is a common misconception that alcohol makes you sleepy. Actually, alcohol sedates you which is different from making you sleep and, more importantly, it significantly blocks REM sleep, which has the aforementioned important functions.
At Longevity Health & Wellness Hotel (Alvor), we offer a programme called “Longevity Sleep Optimisation”. This involves getting a unique holistic check-up, including a sleep apnea screening. Furthermore, we rebalance and regenerate your holistic health and wellbeing, by regaining your sleep quality with energy, stress management, mindfulness, and meditation therapies.