Most of us know how we feel after we get a good night’s sleep, just like we all know how it feels when we do not sleep enough. When we sleep, we are more pleasant, we have more energy, and comprehension of important details is a whole lot easier. As soon as we don’t get enough sleep, we tend to feel fuzzy, exhausted, out of balance and irritable. We can sense the positive and negative consequences of sleep on our bodies and brains, but we may not know why we sleep and how important it is to our health and wellness.
What’s the purpose of sleep?
How much do doctors and sleep scientists know about the way we invest early half our lives? There are several theories as to why humans sleep, check them out below:
Most Common Sleep Theories
Theory 1: The Inactivity Theory
Decades of research have proven that sleep is fundamental to life. All living creatures need sleep and show deficits in working without it. There are numerous theories as to why do we sleep, and why we will need to spend so many hours doing so.
The Inactivity Theory describes sleep as adefensive mechanism that keeps human beings safe during the night. The sleeping force could have evolved in response to the vulnerability to predators and also the disadvantage of not being able to see clearly in the dark. This theory can be traced all the way back to our cavemen ancestors, as clearly, their environment was very different than the world we currently live in.
The Inactivity Theory is supported by the idea that human beings that were not as vulnerable during the night had a competitive edge compared to those who had been awake and moving around. Nighttime activity could be correlated with increased risk of mishaps and vulnerability to predators.
Sleep might have been particularly protective to infants and children, as they would have been more likely to become lost or put in the line of danger during the night.
Inactivity may be the reason sleep evolved to last a complete night, through the hours of maximum darkness and susceptibility. Sleep through the night might have also evolved to conserve activity to be used during the most useful time in the 24-hour cycle: the day time hours, as this is when food and prey are most easily accessible.
Theory 2: The Energy Conservation Theory
Evolution may have given preferential treatment to our human ancestors and animals that stayed static during the night and throughout portions of the day. While humans were evolving as a species, food was often scarce and prey less accessible, making conservation of energy and calories important to survival.
Sleep not only conserves our existing energy, but it also lessens the need to eat extra food during the hours while the body is resting. Digestion is actively happeningwhile humans sleep, and metabolism can decrease by as much as 10%. Core temperature also drop and demand for calories to drop as well. This process decreases the need for energy even more.
Non-REM sleep and body temperature regulation evolved in precisely the exact same timeframe, suggesting to some doctors and scientists that energy conservation has been an important element in the growth of both mental and bodily functions.
Even though the blood pressure, heart rate, and brain activity elevate above non-REM sleep amounts during rapid eye movement sleep, the muscles become paralyzed, which prevents the acting out of what is happening in your dreams and reduces the output of energy.
This theory may be related to The Inactivity Theory. Sleep may be a defensive mechanism that shields the body from predators and injuries as well as the useless cost of calories.
Theory 3: The Restorative Theory
The rates of protein synthesis are higher during sleep. This makes sleeping essential to the healing process.
The brain experiences its own kind of repair during the sleep cycle. Sleep is essential to the restoration and preservation of immune function. The link between sleep and your immune system is supported by several studies that demonstrate how creatures lose all immune function when deprived of sleep.
Adenosine, a by-product of cell activity and energy intake, causes sleepiness as levels increase in the brain during daily activity. The feeling of wanting to sleep increases along with levels of adenosine, which then begin to decline once sleep happens.
Advantages of sleeping:
Our brain is a remarkable and complex organ capable of retaining and understanding a plethora of information as we go about our day. However, the mind stores ideas first to be processed afterwards.
While we sleep, the short-term memories that we have generated during the day are subsequently transferred to long-term memory during consolidation. This is precisely why we keep information better after getting a fantastic night’s sleep.
The mind’s superfluous information removal system is more active during sleep. The process of sleeping restores the mind by eliminating naturally occurring waste fats called beta-amyloid.
As we go to sleep, we are helping our own body break and save energy. It is during this phase when our lungs and heart do not work as tirelessly as when we are awake. This gives our organs a vital recharge.
Time to Recover
Sleep is believed to be the period where the cells in our body fix themselves from the harm caused during waking hours (or to help get rid of that hangover from too many glasses of Prosecco).
Mammals that have high metabolism rates, this includes us humans, tend to sleep for longer periods of time. It’s believed that we input this resting phase so our energy reserves can be replaced and replenished.
Burn those Calories
Sleeping an extra two hours burns around 300 calories. This may be because when we’re sleeping, we are not eating which allows for the body to burn off excess energy.
A study conducted at the Hendrix College in Arkansas revealed that those who slept two hours longer ate significantly less thus decreasing their calorie intake around 300.
Build up those Immunities
Our circadian rhythms play a part in our sleep-wake cycle and work to improve our immune capabilities.
As stated before, it’s during this rest period where our bodies work to repair themselves. It is also while we are sleeping that our immune systems enhance themselves to protect our health and well-being.
What happens if you don’t sleep?
The negative ramifications of not getting enough sleep may be useful in demonstrating the impact of sleep on brain functionality. When you go without adequate sleep, the brain quickly suffers cognitive deficits, which may include but are not limited to:
Along with its effects on memory and brain functionality, sleeping may have other wide-ranging physical and mental effects. It could check links between the brain and systems across the body, like the digestive and cardiovascular systems. Sleep’s effect on the immune system is so significant that vaccines emphasize a more powerful immune response in recipients who were well-slept than those that are deprived of sleep.
How Many Hour of Sleep do you Need?
It’s important to keep in mind, that requirements vary from person to person. However, there are some general rules of thumb you can follow to guarantee you are getting enough sleep. On average, a healthy adult needs seven to nine hours a night. You might feel like those five to six hours are enough to get you through the day, and maybe they are, but keeping that habit can lead to chronic sleep-deprivation. If you have children or teenagers, they need even more sleep. But oddly enough, once you are older than 65, you only need seven to eight hours.