Updated: Nov 19, 2019
Sleep is vital for everyday function. Without sleep, our bodies revolt and we feel it in subtle ways. Chronic sleep deprivation can leave lasting scars in our bodies. Sleep deprivation affects each part of the body differently, but like anything else, the mind goes first.
"The mind is a very active metabolic area. When it works full time, it generates toxic products." Much like anything else, too much of a good thing can be bad. Scientists believe that adenosine, which is a byproduct during metabolism might be the toxic metabolite in the brain that needs to be flushed out during sleep. The first sign of sleep deprivation is a sluggish mind. It is your bodies way of telling you to get some rest. With a sluggish mind comes a slowed reaction time that nearly triples and is about the same as being legally drunk. Memory formation will deteriorate and the creation of new memories shuts off entirely. After 18 hours of being awake, decision making and spatial awareness deteriorate. At 24 hours you begin to have microsleeps; your brain puts itself to sleep for 10-20 seconds at a time, even if you are awake and talking. During this time of microsleep you become cortically blind; unable to process the visual information around you. You lose increments of time which become worrisome. After 35 hours of being awake, you begin to behave irrationally. You jump to conclusions and become judgmental without filtering the information at hand. This happens because the amygdala becomes more reactive to negative stimuli while it limits communication with the part of the brain that regulates emotion. Longer than 48 hours causes psychosis-like behavior; disconnection from reality, outbursts and rambling. If you push it a little longer and go a few days, the consequences can be deadly.
Sleep is a natural blood pressure medication that allows the blood pressure to drop back down after a stressful day. Every day we encounter situations that overwhelm us and our blood pressure begins to rise. Without sleep, our blood pressure will keep rising, which can be lethal. This increases the risk of heart attack, stroke, and heart disease. Sleep reboots the system and allows the body to prepare for the next day. Studies have shown that after daylight savings, there is an increase in heart attacks by 25 %, but during the fall when we gain an extra hour, there is a decrease of 21%.
Where hormone production is concerned, sleep is vital for levels of testosterone and energy. Longer than 18 hours of sleep deprivation can cause low levels of testosterone, but this can be returned back to normal with a good night's rest. The real problem begins when sleep deprivation becomes chronic, lasting from weeks to years, less than 5 hours a day. Studies have shown that this drops testosterone levels by 10-15%, which is significant compared to the normal drop each year of 1-2% for healthy individuals. "A week of bad sleep will age you a decade."
The immune system is very vital for fighting off infections, but when this becomes affected by sleep deprivation, health conditions begin to arise. Being awake longer than 18 hours causes overproduction of pro-inflammatory proteins associated with heart disease. Immune system cells begin to decrease because your body becomes deprived to make more. Sleep deprivation that lasts longer causes the body to have a harder time producing natural killer cells that fight off cancer and virus-infected cells. Studies have shown that just one night of bad sleep reduces the amount by 70%. Poor sleep can increase the risk of cancer. "In 2007, The World Health Organization deemed night-shift work a probable carcinogen."
If the body malfunctions, mental performance becomes significantly affected as well, more so than physiological. In long endurance or team sports that involve a more cognitive component, your mind will begin playing tricks on you. Although physically you will be able to carry out the event, mentally you might be a little foggy. Sleep is not something to take lightly. It is important for health. Without sleep, we would resemble a bunch of zombies.