Sleep apnea is the name of a physical condition that occurs during sleep. It happens when the airway in the throat becomes obstructed by the tongue when it falls back during sleep and cuts off the flow of air to the lungs, essentially suffocating the person for a brief time until the body reacts to the lack of air. This can be from 10 seconds to over a minute. Often the person awakens for a short period of time, possibly finding their heart racing or choking, but unaware of what has happened and then quickly goes back to sleep. Or the person may not awaken at all. This is a cycle that can happen over a hundred times per night.
This condition occurs during the REM stage of sleep. REM (rapid eye movement) is when we dream and is the most beneficial phase of sleep because it is when healing hormones are released and cells repair themselves. REM sleep should account for 20-25% of the overall sleep time in normal conditions. So if someone sleeps an average of six hours per night, REM should account for one and half hours approximately.
However, sleep apnea disrupts REM sleep.
During REM, the brain sends a signal to paralyze all muscle activity so we cannot act up on our dreams, like waking up and walking away. Unfortunately, this also causes the tongue to fall back and block the airway if the person does not have enough airway stability and starts this cycle of air deprivation/choking/going back to sleep, deprivation/choking/going back to sleep, deprivation/choking/…
The benefits of REM sleep are then denied to the person.
But not only this, a drastic decrease of the oxygen saturation levels in the blood occurs. When you are in a hospital and your blood oxygen saturation level falls below 90%, they put you on oxygen. Yet, people with serious sleep apnea have been discovered to have blood oxygen saturation levels as low as below 60%. If you, right now, held your breath for as long as you can, your blood oxygen saturation level would not fall below 92%. So this is serious.
These two factors lead to other serious physical conditions such as high blood pressure, excessive day time sleepiness, risk of developing Type 2 diabetes, mood alteration, lack of concentration, strokes and even heart attacks. It is also related to car accidents.