Sleep health science

There is no "standard sleep template" that is universally applicable. As long as you don't feel obviously tired after waking up, your energy can support work, study and daily activities during the day, and you maintain a regular pattern for a long time, it is your healthy sleep.

Have you ever had this experience? I came across a piece of popular science that said, "If adults don't sleep enough for 7 hours a day, their life expectancy will be shortened." I happened to only sleep for 6 and a half hours the day before, and I felt uneasy the whole day. Even if I had no problem with my energy, I always felt that I was already "damaging my body." I met a 28-year-old back-end programmer a while ago. He has been sleeping at 1 a.m. and waking up at 6:40 every day since college. Calculated, he sleeps less than 6 hours a day. All the indicators in the annual physical examination are normal, and he can write code continuously. I didn't let my mind wander much for 6 hours. Last year, I followed the trend and tried to get the "7 hours of golden sleep" by lying in bed at 12 o'clock every day. Instead, I suffered from insomnia for a week in a row and felt dizzy during the day. In the end, I had to change back to my original schedule, and I felt comfortable immediately.

In fact, there has always been controversy about sleep duration. The updated guidelines of the American Academy of Sleep Medicine in 2015 do recommend that people aged 18-64 years old maintain 7-9 hours of sleep. However, a 2022 tracking study by the Stanford University Sleep Research Center also pointed out that about 10% of people carry the DEC2 short sleep gene and only need 4-6 hours of sleep a day to meet their body needs. Forcibly extending sleep time will disrupt their sleep cycle and reduce sleep quality.

And everyone has been arguing about "staying up late is harmful to the body" for several years, but it is not absolute. The current consensus in the field of chronobiology is that the regularity of work and rest is far more important than the fixed template of "early to bed and early to rise" - if you are a naturally night-time person, going to bed at 2 a.m. and starting at 10 a.m. every day, sleeping for a sufficient length of time and not waking up in the middle, the negative impact on your health is actually far less than a "chaotic schedule" of going to bed at 10 a.m. today and going to bed at 2 a.m. tomorrow. Of course, I have to be honest here. If you are forced to stay up until 2 o'clock and have to get up to go to work at 7 o'clock the next day, that is another matter. This kind of long-term sleep deprivation is definitely harmful to the body.

When it comes to insomnia, many people's first reaction is "lying down and counting sheep, you will always fall asleep." In fact, the intervention ideas in different fields are quite different. Mainstream cognitive behavioral therapy (CBT-I, which is the current first-line solution for insomnia intervention) will suggest that if you lie down for 20 minutes and still don’t feel sleepy, simply get out of bed and go to a dimly lit area to do something less stimulating, such as reading two boring professional books, and then go back to bed when you feel sleepy. The core thing is not to bind "bed" with "anxiety about not being able to sleep." ； However, the sleep intervention ideas of traditional Chinese medicine are different. It is recommended not to get out of bed when you can't fall asleep. Especially in winter, you are prone to wind and cold when you get up. You can try to focus on breathing and slowly slow down the breathing rate. Don't deliberately think "I want to fall asleep." When your mind is empty, you will naturally feel sleepy. There is no absolute right or wrong between these two methods. You can try them both and decide which one suits you best.

I chatted with the attending physician at the city sleep center before, and he said that people in the industry would not criticize themselves for their sleep standards. They would catch up on sleep the next day when working night shifts, and would wake up after sleeping for 4 or 5 hours, and would not lie down for 7 hours. On the contrary, they rarely have sleep anxiety.

As for melatonin, which everyone often hoards, it is really not a magic drug for sleeping. Its essence is to regulate sleep phase. It is only useful for people with jet lag or delayed sleep phase (that is, people who habitually stay up until two or three o'clock to fall asleep and cannot fall asleep if they want to go to bed early). For ordinary people who only have occasional insomnia, taking melatonin is not only useless, but long-term consumption of large doses may inhibit the secretion of melatonin, making it harder to fall asleep.

To be honest, too many people nowadays put too much pressure on sleep. They set multiple alarm clocks to force themselves to go to bed early. They become anxious when they don’t sleep for a long time. Instead, they fall into a vicious cycle of "the more they want to sleep, the more they can't fall asleep". Sleep itself is the most natural physiological need of the human body, just like eating and drinking. Some people eat more and some eat less. As long as your body feels comfortable, there is no need to be tied to various "gold standards". After all, only you know best whether you slept well or not, right?