One saying is that the ancients thought that the west was the direction of the western heaven. If the head was facing west, it would symbolize "going west", which is the legendary driving crane to the west. In addition, in ancient times, people believed in souls. As the saying goes, people have three souls and seven souls, and the soul leaves the body when sleeping. This is also the reason why the ancients believed in dream interpretation. If your head faces west, you will be thought dead by the kids in hell and your soul will be taken away. People will die naturally without three souls and seven souls. So the ancients thought it was unlucky, so they said not to sleep facing west, but this statement is obviously a very superstitious thought.
There is also a saying that the ancients believed in the theory of "harmony between man and nature" and thought that heaven and earth were a big universe, while human body was a small universe. The law of human behavior should follow the law of the natural operation of heaven and earth, that is to say, the sunrise is in the east and the sunset is in the west, and so is man. The east is full of vigor and the west is decadent. The head is the foundation of the human body and the place where the yang is located. If the head is facing west when sleeping, the whole person's head is in a groggy state, and drowsiness is upwelling, it will also affect a person's yang, leading to the lack of yang in the body and the invasion of pathogens, which will lead to the occurrence of diseases, affect health and shorten life expectancy.
Although these are superstitious statements, we should also pay attention to our sleep situation, adjust our sleep posture when the quality of sleep declines, and ensure adequate sleep.