No one doubts the importance of sleep to our lives. For this, it is enough that we spend a sleepless night to see how the lack of sleep brings great consequences to our day. In fact, this is the reason why sleep medicine has gained such importance in recent years: sleep has become an important medical issue for medicine where the impact of lack of sleep on health has been noted.
Still, sleep deprivation currently appears to be being glamorized. First came the reports, often unproven, that great geniuses and scientists slept very few hours a night; seeking to suggest that sleep deprivation increases creativity. More recently, digital influencers have conveyed the idea that sleep deprivation is the path to professional success as a way to increase productivity. Before we start, know in advance: These things are big lies.
But what exactly is sleep deprivation? This post will explain everything to you, including the main health effects of lack of sleep.
DEFINING SLEEP DEPRIVATION
In a very general definition, we are sleep deprived when we sleep less than we would like or need. For an adult this would be somewhere around 7-8am (although there are exceptions, which we'll cover in a future post – stay tuned!). But sleep deprivation can be broken down into more specific conditions:
• Extended wakefulness: It is total sleep deprivation, given by cases where sleep does not occur for a certain period of time. For example, a police officer who works 24 hours a day is on an extended watch case. If the total time he will be awake is calculated, we can easily reach something close to 36:00. The same goes for truck drivers working longer than usual, or in the case of a student who has decided to stay overnight to study for a test. This case is always acute, as it is practically impossible to be completely sleep deprived for a few more days.
• Sleep restriction: It is the usually chronic condition in which you can sleep every day, but not enough. Think of a person who comes home at 11 pm and has to wake up at 4 am because of their two jobs. She will only get 5 hours of sleep per night, which means that each day she will accumulate a sleep debt of 2-3 hours. This condition is increasingly common in big cities, as it is a reflection of the troubled routine and excess of activities. The big point is that this case is usually chronic.
• Sleep fragmentation: Occurs when sleep is “stuck” throughout the night, causing us to not be able to deepen it. Although the total sleep time is not as affected in this case, the quality of sleep is quite compromised. In many cases, sleep becomes very shallow and the percentage of important sleep stages is reduced (such as slow wave sleep and REM sleep). Sleep fragmentation is common in many cases. The main one is sleep apnea, in which with each obstruction in breathing we need to surface our sleep to be able to breathe again. This makes the sleep of a person with apnea never get deep enough. It is also common in pregnant women, who have fragmented sleep due to several anatomical and physiological changes (such as difficulty sleeping in usual positions, back pain, baby movements, need to go to the bathroom, among others). In addition, the use of some medications, chronic pain and an inadequate sleeping environment (too much noise, high temperature, etc.) can fragment sleep.
HOW MANY PEOPLE ARE SLEEPING DEPRIVED?
Everyone! Think about your surroundings, there is no one who has never had at least one sleepless night. Of course if we think about chronic conditions the percentage is a little lower, but it's still very common!
More precisely, up to 44% of people have insufficient sleep, with 30% of the population getting less than six hours of sleep per night. In addition, in the last five decades, sleep time per night has decreased by 2 hours. This means that while your grandparents slept 8 hours a night, you sleep 6 hours.
HEALTH CONSEQUENCES OF SLEEP DEPRIVATION
Sleeping badly for one night is a commonplace in our lives. But those who think they can sustain a life of little sleep without consequences are wrong. The truth is, lack of sleep affects our entire body. Here are some effects below:
Mental health: Lack of sleep completely alters our behavior. It only takes a few hours of sleep deprivation to make us feel more anxious, impulsive and inattentive. This triad of consequences is the cause of many side effects. For example, sleep deprived people are unable to judge risks adequately and end up making wrong decisions or engaging in risky behavior (impulsivity and anxiety effect). Furthermore, due to lack of attention, work and car accidents are much more common in people deprived of sleep and the effects are comparable to those in intoxicated people.
Cardiovascular Health: Overnight our blood pressure and heart rate should decrease by at least 10%. This is proof that it is during the night that the heart “rests”. A person deprived of sleep or subject to chronic sleep restriction is unable to give this rest to the heart. Imagine a car that works 24 hours a day. Surely this car will fail sooner than another that runs only 8 hours a day and spends the night in the garage. That's exactly what happens to the heart: one who doesn't rest at night will eventually fail sooner. It is already known that sleep deprivation and sleep disturbances are closely related to hypertension and increased chances of having a heart attack or other heart problems.
Metabolism: Imagine that you went to a party and spent the night awake. When you leave, you are hungry and decide to eat something. Have you ever seen someone like that ask for a serving of salad? Certainly not! In these conditions we tend to foods rich in fat and carbohydrates. Most of the time we end up looking for that greasy hamburger or pizza... What happens is that sleep deprivation alters hormones that control our hunger and satiety, making us look for heavier foods, even if we don't need them. This explains why the sleep deprivation epidemic and the obesity epidemic go hand in hand. In addition, lack of sleep is very much associated with one of the main metabolic diseases today: diabetes.
Immunity: If you always have a cold, pay attention: maybe you're getting too little sleep. The immune system needs sleep to function properly, as it is during this period that it ensures its proper functioning. Sleep deprived people are actually more susceptible to viruses. This can have some important consequences: it is now known that if we get vaccinated while we are sleep deprived, the immunization may not work.
Sexual health: Lack of sleep can have a huge impact on sex life, as it alters both hormones and people's behavior. Sleep deprived people have diminished sexual satisfaction and interest. Especially in men, erectile dysfunction has been linked to sleep fragmentation caused by apnea.
Central Nervous System: The brain also needs sleep to work. But unlike the heart, which rests while we sleep, the brain works a lot during sleep. It is during this period that the brain clears the impurities that accumulate during the day, enabling it to be able to function well the next day. In sleep-deprived people, these impurities can build up and affect the functioning of neurons. It is important to remember that some diseases, such as Alzheimer's disease, happen precisely because some substances are not removed and accumulate in the brain. This explains why Alzheimer's is more common in people who are chronically sleep-restricted. Furthermore, sleep deprivation can alter our cognition, explaining memory difficulties, learning concentration and shorter reaction time in sleep-restricted people.
Many other health consequences can be listed as an effect of sleep deprivation: decreased resistance to pain, decreased muscle strength, increased inflammation, increased chance of having strokes, depression and anxiety. See more in this TED by Claudia Aguirre.