Children’s height depends 70% on their parents’ genes, 30% on their genes, and among these 30% external factors, the latest research shows that sleep ranks first in terms of its effect on height, beyond exercise and diet. So if you want your child to grow as tall as possible, it’s best to put your child to bed at 8:30. Most primary and secondary school students in Guangzhou do not get enough sleep According to the Ministry of Education’s “Guideline for Health Education in Primary and Secondary Schools”, primary school students should get 10 hours of sleep a day and junior high school students should get 9 hours of sleep a day, while a 2009 survey by Professor Zhu Shun Ye of the Department of Pediatric Endocrinology at the Third Hospital of Sun Yat-sen University showed that primary and secondary school students in Guangzhou get half an hour to an hour less sleep. ”It used to be thought that 70% of a child’s height is determined by heredity, but now the view is that the role of acquired factors is increasing, and diet, exercise and sleep have even become the main causes in some cases, especially sleep.” In terms of the order of influence, it was previously believed that exercise, sleep and diet were the three influences, with exercise taking first place, and now sleep has been recognized as the first influencing factor. Growth hormone is mainly secreted at night while sleeping “Growth hormone is an important factor affecting human height, it is secreted in a pulsatile manner, mainly at night, and the more it is secreted, the more it helps growth.” Professor Zhu Shun Ye said that the secretion of growth hormone reaches its highest from 9 p.m. to 1 a.m. the next day, especially around 10 p.m., and can reach 5-7 times the amount during the day. And one or two hours before and after 6 am, there is also a small peak of growth hormone secretion. Once the late sleep is missed, it can never be made up. The secretion of growth hormone has a prerequisite, deep sleep. If you go to bed but do not fall asleep, or fall asleep but do not enter deep sleep, the secretion will be greatly reduced. Therefore, if you want your child to grow taller, it is better to go to bed before 8:30 pm, and not later than 9:30 pm, and get up after 7:00 am. You should know that growth hormone is secreted by the human pituitary gland, which has a huge workload. In addition to secreting growth hormone, there are also sex hormones and adrenocorticotropic hormones, so it does not secrete growth hormone 24 hours a day. However, infancy is an exception, as growth hormone is secreted continuously during the day and night, so infants before the age of 1 year grow particularly fast. When they enter early childhood, growth hormone secretion is mainly concentrated at night when they go to sleep.