According to the principle of hand diagnosis in traditional Chinese medicine, normal nails should be ruddy and delicate, tough and curved, smooth and shiny, and the crescent on the nail cover is clear. The crescent moon is a "barometer" of whether the human body is energetic and healthy. The more energetic, the whiter, and the worse, the more blurred. Generally speaking, the crescent moon is about one-fifth of the area of a nail, with clear edges. When a person's body has a disease, it can generally be displayed through the crescent moon, or the color changes, or the crescent moon decreases. When a person's body recovers through conditioning, the crescent moon will slowly reappear. There is no crescent moon before the child develops, so parents don't have to be too alarmed. When the child is well developed, the crescent moon will naturally grow out. In addition, adults have too much nightlife and sex life, and the crescent moon will wither and it is difficult to grow. Therefore, it is recommended not to stay up late and not to indulge for a long time. Experts say that the fewer new moons, the worse the energy, the worse the physique and the weaker the immunity, which also means that people are more prone to fatigue. If there is no crescent moon, it doesn't necessarily mean that you are sick, but it should be noted that people without crescent moon are often not sick, and a disease is often more serious. In addition, only the crescent thumb friends pay attention, indicating that your body energy may have begun to be insufficient, and the disease is not far from you. If the crescent moon is found to be reduced, protein and black food, such as black rice and black fungus, can be supplemented. Besides proper exercise, try to keep fit. To judge whether a person suffers from a certain disease, other factors should also be integrated, and it can be determined through inspection and demonstration by all parties, so there is no need to panic because of the change of crescent moon.