How We Sleep

Photo: Bókafélagið

Translation: Sindri Snær Jónsson

"An intimate and bidirectional association exists between your sleep and your immune system. Sleep fights against infection and sickness by deploying all manner of weaponry within your immune arsenal, cladding you with protection." With these words, Dr Matthew Walker opens the Russian version of his book Why We Sleep: The New Science of Sleep and Dreams. Walker is a professor in neuroscience and psychology at UC Berkeley, where he heads the Center for Human Sleep Sciences. He is also a former professor of psychiatry at Harvard University. 

Vaccination alongside immunity

The better and more correctly we sleep, the healthier we are. This is very important to keep in mind, especially in the age of COVID-19, as the individual’s immunity factors into whether they get sick and how severe the virus gets, and the immunity can depend on one’s sleep health. Here I’d like to reiterate that the vaccine helps the human immune system beat COVID-19, but it doesn’t do it by itself. More than twenty years ago, when Dr Michael Walker had just started studying sleep, a Russian man named Denís Semeníkhín experienced how sleep affects the immune system. Semeníkhín is a sports YouTuber, health- and fitness journal writer, and a former journalist for Men’s Health magazine. 

The athlete’s battle with sleep

Photo: Dení Semeníkhín

Semeníkhín felt he spent too much time sleeping, so he decided to sleep for only 4,5 hours a night to get more work done during the day. He felt good. He worked a lot, worked out at the gym, but in half a year, he got sick with a rare disease - he suffered a blockage in his salivary gland. Later, he got a nodule in his eye for the first time. An athlete who had never been sick had suddenly contracted a rare sickness. Semeníkhín deduced from there that his illness may have resulted from bad sleeping habits, although he didn’t feel it affected him in any other way. After he started sleeping for eight hours again, the diseases ceased to be. Semeníkhín’s conclusion was thus: within every living being is a weakness, and if the being is under a lot of pressure, such as getting too little sleep for a long time, these weaknesses start to come to the surface. 

An hour’s worth of sleep

A few years ago, a statistic showing users’ sleeping habits became popular on Facebook. The statistic showed that an hour’s worth of sleep before midnight is heaps more effective than an hour after midnight. Semeníkhín’s point is very similar, as he chose to sleep between 22:30 and 3:00. He believed in the effects of only sleeping for four hours but during the most critical hours of the day. Dr Matthew Walker confirmed in his book that you should sleep for eight hours and that it doesn’t matter when you sleep: from 19:00 to 3:00, or from 00:00 to 8:00. Scientists at the University of Pennsylvania and Washington State University have proven the need for eight hours of sleep. 

Studies in The United States

Researchers amassed 48 healthy men and women who all slept an average of 7-8 hours a night. Then they were put into four groups: 

  1. Had to stay awake for three days straight. 

  2. Slept for four hours a night. 

  3. Slept for six hours a night. 

  4. Slept for eight hours a night. 

All but the first group slept according to their given guidelines for two weeks. While the study lasted, the participants’ physical and mental performance were analyzed. Those who slept for 8 hours did well, but those who slept for four and six hours showed a cognitive decline, lack of attention, limited mobility and so on. The four-hour group showed the worst results. 

Lack of sleep builds up

The researchers concluded that the lack of sleep had been built up. A week after the study, a randomly picked 25% of the six-hour group fell asleep during the day. After two weeks, they started looking drowsy as if they hadn’t slept for two days at a time. This means that sleeping for six hours a night for two weeks equals not sleeping for two days in a row. Yet, the most interesting thing is that the participants did not notice the change in their behaviours. In fact, many aspects factor into this illusion. Good lighting in the office, coffee, funny conversations with co-workers - these all make you feel like everything is fine. However, drowsy behaviour is not the worst consequence of getting insufficient sleep. The research that Dr Matthew Walker refers to shows that those who lose sleep regularly are more at risk of getting depression, anxiety, diabetes, cancer, heart disease and stroke. It seems that hanging on TikTok until 3:00 in the morning has its price, right? So, finish reading this article and crawl under your blanket.

LifestyleIgor Stax