What are the dangers of children sleeping late?

Children go to bed late, can cause the following harm: first, affect the child's learning, physical health. Sleep late, the next day to get up early to go to school, resulting in insufficient sleep, often sleepy in class, doze off, concentration is not concentrated, can not seriously listen to classes, for a long time will show a decline in academic performance. The body is in an extremely tired state, resistance decline, easy to get sick. Second, affecting growth and development, the pituitary gland daily secretion of growth hormone peak is between 8 pm and 2 am, between 5 pm and 7 pm. Therefore, in this time period should let the child into a deep sleep state, can improve the secretion of growth hormone, is conducive to children grow tall, and increase the child's memory. On the contrary, the child did not enter a deep sleep state during this time period, the secretion of growth hormone will be reduced, the child will show a long not tall, memory loss and so on.