Although the most fundamental reason why we need daily sleep remains in dispute, health gurus and experts alike can all agree that getting a good night’s rest should be high on your list of priorities.
Sleep is without a doubt, essential to health and survival. Even if you don’t eat very well, you can still expect to live to the age of 76 if you're a man and to about 81 years old if you're a woman. But if you don’t sleep, you’ll likely only survive a couple of weeks – The Guinness Book of Records recognizes the official longest period of unassisted sleep deprivation as 11 days.
Sleep is vital for conserving energy and allowing the body to heal and repair itself from the metabolic stress and toxicity of daily activity. Sleep is also the most important trigger for maintaining healthy biorhythms. Disruption to your intrinsic circadian rhythm (sleep/wake cycle) has been shown to dysregulate your body’s other hormonal rhythms (like your reproductive cycle) and metabolism with insufficient sleep being linked to diseases such as obesity, insulin insensitivity, diabetes, andhormonal and appetite imbalance.
According to the National Sleep Foundation most adults need between 7-9 hours sleep a night. Here’s a quick look at some of the reasons why sleep plays such a vital role in our health:
1. Live Longer
The body heals and repairs itself during sleep so inadequate sleep is is a causal factor for a shorter lifespan.
2. Control Stress
A good night's sleep is a great way to alleviate stress and help stabilize cortisol levels. Insufficient sleep can cause a surge in cortisol making you more prone to stress and more likely to suffer from low energy which increases your chances of giving in to those calorically dense but nutritionally empty temptations in the vending machine!
3. Improve Memory
If you are trying to learn something, whether it’s physical or mental, you learn it to a certain point with practice, but something happens while you sleep that makes you absorb that information or pattern better.
4. Recover Better
Do you want to lift more, run faster, get more pull-ups? Sleep stimulates your body’s release of human growth hormone (hGH) which helps your muscles recover and grow.
5. Improve Performance
Good quality sleep is nature’s natural sports performance enhancer as it improves your speed, hand-eye coordination, reaction time and muscle recovery. A study in the Journal of Strength and Conditioning Research found that sleep deprivation actually reduced muscle strength and power the next day.
6. Manage your weight
Lack of sleep causes a surge in production of the hormone ghrelin which boosts appetite. It also causes a decrease in the hormone leptin which signals feeling full. So a lack of sleep can make it EXTREMELY difficult for you to control your appetite and manage cravings as you struggle to resist the urge to eat in response to these hormones. Studies suggest that people who sleep fewer than 6 hours per night gain almost twice as much weight over a 6-year period as people who sleep 7 to 8 hours per night.
7. Improve Creativity & Productivity
When you sleep your brain reorganizes and restructures, giving your mind more room to grow and be free! Sleep allows you to access the vast amount of information and knowledge in your brain that doesn’t immediately come to mind. So that old saying of “sleeping on it” actually helps in solving a new and seemingly difficult problem. All in all, our levels of concentration, attention, focus and work efficiency, are at their peak when we’re well rested and fresh. Google understands the productive value of sleep and went as far as installing sleeping pods in their offices sotheir employees can take performance-enhancing power naps!
8. Improve your Mood
Think about the last time you slept badly. Do you remember feeling cranky, irritable and frustrated the next day? A lack of sleep makes you more vulnerable to stress and anxiety, conversely getting an optimal amount of good quality sleep will improve your level of wellbeing and overall vitality.
Sleep and your Hormones
Adequate sleep helps to regulate cortisol levels as well as blood sugar stabilizers like insulin and sex hormones like testosterone. Let’s take a quick look at the significance of sleep on some of our key hormones.
Cortisol is also commonly known as the stress hormone, as it’s responsible for responding to both physical and emotional stress. The production of cortisol is essential as a mechanism for human survival but when produced outside it’s optimum range (too much or too little) it can have extremely negative effects on our health.
Cortisol is known to impede healing, increase risk of injury, worsen memory, increase blood pressure, imbalance blood sugar and cause weight gain amongst other things! Those who are chronically stressed run the risk of developing the following health issues:
- increased blood pressure;
- blood sugar imbalances;
- decrease in bone density;
- depressed mood;
- digestive problems;
- heart disease;
- weakened immune system;
- impaired memory, learning, and cognitive performance;
- loss of muscle tissue;
- sleep problems;
- reduced thyroid function;
- slowed wound healing and
- weight gain.
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Insulin is an important regulator of blood sugar levels. When your blood sugar level is high, for instance after eating a meal, insulin is released and attaches to sugar molecules (glucose) in the blood. It acts as a “key”, unlocking cells in the body so glucose can be removed from the blood and stored to be used as energy when needed later. Insulin stops your blood sugar levels from getting too high (hyperglycemia) or too low (hypoglycemia).
Insufficient sleep can reduce insulin sensitivity, meaning your cells don’t respond as well to the production of insulin, so glucose levels remain high in the blood instead of being moved into cells for storage. Chronic hyperglycemia is the defining characteristic of Type 2 Diabetes and a contributing factor to obesity.
Testosterone is essential for building strength, muscle mass, bone density and not to mention boosting your libido! Testosterone deficiency is associated with poor concentration, fatigue, low energy and a decrease in athletic performance. According to a study published in the Journal of the American Medical Association, a group of men who slept less than 5 hours a night over the course of one week, experienced between a 10-15% drop in their testosterone levels.
Human growth hormone (hGH), the hormone responsible for growth and repair, is typically released during the stages of deep sleep. Five stages of sleep occur approximately every 90 minutes to complete one full sleep cycle. If numerous full cycles of sleep aren’t attained each night, then hGH secretion can decrease and effect mental and physical restoration. For athletes, this often leads to a decrease in performance as the perceived rate of exertion is thrown off, causing you to think & feel like you’re working much harder than you really are.
Sleep deprivation has been directly linked to chronic inflammation as indicated by high levels of hsCRP (a key inflammation biomarker). Inflammation in the body will not only effect our performance but will diminish our ability to make gains in the gym. Inflammation is also thought to be a precursor to many modern ailments such as arthritis, asthma, Crohn’s disease, Alzheimer’s, cancer, diabetes, high blood pressure, cardiovascular disease and Parkinson’s.
Now that you know why getting enough shut eye is so important have a think about whether you’re getting enough – Remember, you want to strive for 7-8 hours a night. How can you create more time or improve the quality of your beauty sleep? Comment below and check out some of these sleep hacking apps in the meantime.