Sub-health refers to a critical state between health and disease. Sub-health can be transformed into a healthy state in a good direction, or it can be transformed into a variety of diseases in a bad direction.
Sub-health state generally refers to a physiological state in which the body shows different degrees of decreased immunity, low physiological function and decreased adaptability, although there are no indicators of organic diseases. In this state, people will feel unwell, unhappy and sometimes have social obstacles. This state between health and disease is called sub-health state. Generally speaking, it is a state in which you feel uncomfortable when you go to the hospital and you can't find anything wrong.