20 hours for newborn +04-65438+ 05 hours for baby.

Preschool children 12 hours, pupils 10 hours.

9 hours for middle school students and 8 hours for college students.

8 hours for adults and 6-7 hours for the elderly.

Middle-aged people are under great pressure, so they should pay more attention to the combination of work and rest and arrange rest and sleep reasonably.

1. Choosing the best lying posture Modern medical people believe that lying on the right side is beneficial to health, because the heart leans to the left side of the chest. When lying on the right side, the muscles of the whole body are relaxed, the chest is not oppressed, and breathing is comfortable, which can ensure oxygen supply for the whole body when sleeping.

2. The best direction Many scholars believe that sleeping with head facing south or north, along the north-south direction of geomagnetism, can produce biological magnetization effect, strengthen bioelectricity, be beneficial to organ function regulation, and be easy to be healthy.

3. Optimum temperature Generally speaking, people can sleep peacefully at the ambient temperature of 15-24℃.

4. The Best Time According to a survey by the American Cancer Society, adults who sleep for 7-8 hours a day live the longest, and those who sleep less than 4 hours have twice the disability rate as normal people. People who sleep more than 10 hours a day are not good for their health.

5. The best pillow height for adults is 10- 15cm, which is equivalent to a sleeper's shoulder height.

6. The best bed As far as the physiological bending requirements of the spine are concerned, Simmons bed and spring bed are not ideal beds. The best bed is a wooden bed, followed by a mattress on a brown shed bed, which can keep the spine in a normal state.