Sleep health core information and explanations

The sleep cycle is complete, the daytime energy is high after waking up, and the long-term work and rest rhythm is stable. The requirements spread on the Internet such as "must fall asleep before 11 o'clock", "must sleep for 8 hours a day", and "must take a half-hour nap" are mostly one-sided conclusions divorced from individual differences. **

Many people may think this statement is a bit counter-intuitive. After all, they have been taught since childhood that "early to bed and early to rise are good for health." During my previous sleep consultation, I met too many people who were anxious about sleeping due to these strict standards. For example, last year a girl who worked in cross-border operations came to me and said that she had been suffering from insomnia for more than half a year and felt groggy every day. Her thyroid and hormones were checked and they were all normal. When I asked her, I found out that she had read a popular science article and said that staying up late at 11 o'clock would "damage your liver" if you didn't sleep at 11 o'clock.

Interestingly, regarding the controversy over work and rest time, research in different fields has indeed not come to a unified conclusion. Traditional Chinese medicine theory has always emphasized the importance of "midday nap". It is believed that 23:00 to 3:00 am is the running period of the gallbladder and liver meridians, and sleeping deeply at this time can nourish qi and blood. ； The consensus of the Modern Sleep Medicine Association is that as long as your schedule is fixed for a long time and your circadian rhythm is stable, the secretion of melatonin and cortisol will adjust according to your schedule. Even for night shift workers who stay up at night for a long time, as long as they get enough sleep every day, the impact on their health will be far less than that of people who jump back and forth in their schedules. Both statements are supported by corresponding clinical data. There is no absolute right or wrong. The core is whether your own body can adapt.

Let’s talk about the unfamiliar “complete sleep cycle” first. To put it bluntly, the state after you fall asleep is not a pool of stagnant water, but a cycle of “light sleep-deep sleep-rapid eye movement (REM) sleep” every 90 minutes or so. When you wake up after a complete cycle, you are the most refreshed. Just like when you set an alarm clock, if you happen to be woken up in the deep sleep stage, even if you have slept for 7 or 8 hours, you will feel dizzy and bloated when you wake up, and you will not be able to recover for a long time. ； On the contrary, sometimes I only slept for 4 and a half hours (exactly 3 complete cycles) when I had to catch an early flight, and I felt very energetic when I woke up. This is the reason. If I want to get up early, I will set the alarm clock in multiples of 90 minutes. I personally tested it and it is much more comfortable than getting up at a random time.

As for the standard of "full of energy after waking up", it is actually the most intuitive basis for subjective judgment. Many people are always anxious about how long they sleep. In fact, as long as you don’t have to drink more than two cups of coffee during the day to stay alive, your mind won’t wander and make you sleepy while sitting, and you can concentrate when working and studying, even if you only sleep 6 hours a day, it’s totally fine. Here is a point that is still controversial in academic circles: Some studies believe that long-term sleep less than 7 hours in adults will increase the risk of cardiovascular disease. However, other studies have confirmed that 1%-3% of the population are "short sleepers" who are born with the short sleep gene. They only need to sleep 4-6 hours a day to stay energetic without any health risks. So you really don’t have to judge yourself by other people’s standards. If you sleep for 6 hours all year round, you will wake up naturally and be energetic all day long. There is no need to waste time by lying down for 8 hours.

The third core criterion, "long-term stable work and rest rhythm", is really much more important than whether you go to bed early or late. For example, if you go to bed at 12 o'clock and start at 8 o'clock every day on weekdays, then suddenly stay up until 3 o'clock on weekends, and sleep until 1 pm the next day, this "social jet lag" will do more harm to the body than going to bed at 1 o'clock and starting at 9 o'clock every day. It is equivalent to giving yourself a two-hour jet lag every weekend. Of course, you will suffer from "vacation syndrome" on Monday. When I help many users adjust their sleep problems, the first step is never to let them go to bed early, but to fix the time to get up. No matter what time they go to bed the night before, they must get up at that time the next day. Even if they are extremely sleepy, don’t lie down to catch up on sleep. If you persist for three or four days, you will naturally feel sleepy at night, and the rhythm can be adjusted quickly. It is much more effective than taking melatonin.

As for the questions that everyone usually asks the most, I will also explain them clearly to save everyone's anxiety. For example, “Is it useful to catch up on sleep after staying up late? ”, the answer is useful. If you stay up late once in a while, take a nap of about 20 minutes at noon the next day, or go to bed early for half an hour every day for the next two or three days, you can basically make up for it. You don't have to think that "it takes a week to recover after staying up late", which will put unnecessary psychological burden on yourself. Another example is "Should I never look at my phone before going to bed?" ”, in fact, it is not so absolute. As long as you lower the screen brightness, turn on the night mode, avoid reading too exciting novels and horror movies, and watch relaxing pet short videos and short essays for a while, it can help you relax your nerves. There is no need to force yourself to do nothing for the sake of "healthy sleep". On the contrary, it will make you nervous before going to bed and make you unable to sleep.

In fact, sleep is the most natural physiological need of the human body, just like eating and drinking. Some people eat more and some eat less. Some people like to eat rice and some like to eat noodles. There are so many golden rules that must be followed. Don't be anxious about the various "sleep standards" on the Internet. It's better to sleep comfortably and wake up energetically than anything else. If you really can't fall asleep after lying in bed for more than an hour for more than half a month, or if you still feel drowsy after sleeping for 8 hours a day, then go directly to the sleep department of a regular hospital to see a doctor. Don't buy melatonin or sleep-aid candy on your own, which may disrupt your own rhythm and cause more harm than good.