How long should I sleep every day? For most adults, sleeping seven or eight hours a night is enough. According to a survey by the American Cancer Society, people who sleep seven or eight hours a day live the longest. In contrast, the mortality rate of adults who sleep less than 4 hours a night is higher than180%; Adults who sleep more than 10 hours a night have a higher mortality rate of 80%.
The following are data about human sleep time:
Age, sleep time
20-22 hours for newborns
February baby 18-20 hours
1 year 15 hours
2 years old 14 hours
3-4 years old 13 hours
5-7 years old 12 hours
8- 12 years old 10 hour
12- 18 years and 9 hours
Adult 7-8 hours (not less than 6 hours)
60-70 years old and 9 hours
70-90 years old 10 hour
Over 90 years old should not be less than 10 hour.
Too long sleep, like lack of sleep, will lead to mental fatigue, physical fatigue and decreased metabolic rate. Sleep should not be too long. If you sleep too long, your heart will slow down, your metabolic rate will drop to a very low level, and your muscle tissue will relax. Over time, people will become lazy and weak, and even their intelligence will decline. So people should not sleep too long, 7-8 hours of day and night is enough for adults. If you want to gain health by increasing sleep time, it will be counterproductive, increase diseases and shorten life expectancy.
A survey by Yukio Hatoyama, an associate professor at Nagoya University, shows that people who sleep for an average of seven hours a day live longer, and those who sleep too long or too short have a higher mortality rate.
In the survey of sleep time, men sleep an average of 7.5 hours a day, while women sleep an average of 7. 1 hour. Men and women with the lowest mortality rate sleep for about 7 hours.
People who sleep less than four hours or more than ten hours a day, both men and women, have a high mortality rate. In addition, surprisingly, people always think that "sleeping for eight hours a day" is the most standard, but the survey shows that people who sleep for eight hours have a higher mortality rate than those who sleep for seven hours.
However, some experts in fine medicine pointed out that sleep time actually changes with age and season, so as long as you meet your physiological needs and maintain adequate and high-quality sleep, you don't have to pay too much attention to sleep time, and sleep time must be maintained at seven hours.
Of course, the length of sleep is closely related to long-term habits. Peter I of Russia only sleeps five hours a day, Edison only sleeps two to three hours a day to regain his energy, Napoleon sometimes just takes a nap in a tree to get rid of fatigue, but Einstein sleeps 10 hours a day.
Therefore, whether you get enough sleep varies from person to person. As long as you feel clear-headed and happy after waking up, you can say enough.