The longer you sleep, the sooner you die

　　How long do we need to sleep?

　　I believe we are all familiar with the harm caused by lack of sleep: low energy, slow reaction, memory loss, reduced immunity, and even premature aging of the body? ? The most common statement at present is that an adult should have 7 to 8 hours of sleep, but an experiment at the University of California in the United States came to a sensational conclusion: "Sleeping 8 hours a day will make you die faster." ”

　　The six-year experiment was led by the University of California, San Diego School of Pharmacy and the U.S. cancer Learn to work together. They observed one million subjects aged between 30 and 102 years old. In this experiment, the age, medical history, healthy Conditions, etc. are all taken into account, and they are compared with people who are physically similar to themselves.

　　Studies have found that people who sleep only 6 or 7 hours a day have a much lower mortality rate than people who sleep more than 8 hours a day or less than 4 hours a day. Among them, people who sleep for 7 hours a day have the lowest mortality rate, and even for people who only sleep for 5 hours, this coefficient is lower than that of people who sleep for 8 hours.

　　Although research institutions say that more evidence is needed to prove the causal relationship between mortality and sleep time, it undoubtedly gives us a new reminder: How long do we need to sleep?

　　Sleep is a systematic project

　　actually, sleep It’s not like lying on the pillow, covering yourself with a quilt, closing your eyes for a night, and then opening them again. Eye Waking up is so simple, it is a complex gradual process. Why do we sometimes wake up with our bodies miraculously regaining strength, and other times feel even more tired than before we went to sleep? This is caused by the different depth and state of sleep.

　　Researchers at the University of Chicago, after recording brain waves of thousands of volunteers during sleep, revealed the human body's sleep cycle: During sleep, the human body first enters the slow-wave sleep period, then the rapid eye movement sleep period, and then starts again. There are about 4 to 6 sleep cycles in a night.

　　Those who often wake up at night, or wake up before getting enough rest, have very disordered sleep rhythms. The electroencephalogram shows fast, sharp rises and falls, and suppressed wave patterns at each stage, which are not seen in normal people's sleep.

　　Therefore, only fully carried out 4