Sleep is one if not the most important physiological functions (excluding respiration and cardiac function) of the human body. It is the time the body needs to repair, heal, and replenish itself so you feel rested and rejuvenated the next day. Inadequate sleep inhibits our body’s time and ability to fully repair the wear and tear that has occurred during the previous day. With chronic inadequate sleep the affects begins to accumulate and the body’s physiology begins to alter which leads to problems. Some of the problems include: high blood pressure, heart failure, stroke, obesity, depression, mood disorders, and mental impairment.
- It’s not just sleep quantity, but sleep quality that is important. You can increase your sleep quality by exercising, avoiding light stimulation before bed from a television, Smartphone, iPad; avoid stimulants like coffee or tea (caffeine) in the evening, managing stress (working fewer hours, meditation), and improving your diet. Even simple things like not drinking too much just before bed can eliminate the need to get up to pee in the middle of the night.
Sleep stimulates the release of serotonin. Serotonin is a hormone that regulates mood, appetite, and sleep. Research has demonstrated that pain perception can be either increased or decreased 10-fold depending in part on serotonin levels. Melatonin, a hormone that helps us fall asleep follows a circadian rhythm – it’s meant to be low in the morning and highest in the evening (unless you are on night shifts). Serotonin has the inverse pattern – high in the morning and low in the evening. Light stimulates the release of serotonin and inhibits the release of melatonin. So it is important to get lots of natural light in the morning to increase our serotonin levels which helps us wake up and get going. By contrast in the evening (a few hours before bed) we want to decrease the amount of light we are exposed to, as we want to stimulate the release of melatonin and inhibit serotonin. This means dimming your lights if you can, or turning off the main lights and turning on a lamp or two.
Sleep is a healing and reparative time for the body’s cells. If you do not get adequate amount of sleep your body does not have enough time to repair the wear and tear that you have accumulated throughout the day. If this process continues the damage begins to accumulate until it reaches a point were something has to give. Unfortunately, this can lead to metabolic, psychological, or physical issues in the body which can manifest in a myriad of ways.
Here are some interesting facts about sleep:
The average Australian adult sleep 8 hours per night, and changes position an average of 13 times during this period. If you fall asleep in less than five minutes you are considered to be sleep deprived. Normally it should take between 10 -15 minutes to fall asleep.
Staying awake for seventeen straight hours results in a decrease in motor performance equivalent to someone with a blood alcohol-level of 0.05%.
If you take sleeping tablets such as barbiturates they essentially knock you out which can suppress REM sleep, and if taken longer term can be harmful.Drinking alcohol may help you fall asleep, however, it will be a light sleep and you won’t dream as much.
A new baby typically causes their parents between 400-750 hours of lost sleep in the first year. Unfortunately, there is no easy solution for this problem or than getting a relative to baby sit for a night to at least get one night of restorative sleep.
Inadequate sleep can lead to obesity. Sleep deprivation leads to disruption of hormones that control appetite and metabolism. In the 1960s adult American was getting 8.5 hours of sleep per night, which has since dropped to just under 7 hours in 2008. Obesity concomitantly rose from 13% in 1960 to 34% in 2008.
Sleep helps the brain recall newly learned things. A study by Fenn found that sleep facilitates the recovery and subsequent retention of material learned throughout the day. So sleep can in effect make you smarter.
The take home message here is: sleep is very important! Just because you can function on 4 hours of sleep doesn’t mean you should. Conversely, you should be thinking what amount of sleep will optimise my cognitive, social, physiological functions and well-being?