Nail whitening is the appearance of a white arc on the lower fifth of the nail, which is shaped like a crescent moon, hence its name. The condition of the white part of the nail shows the health condition of the human body. The development of the half-moon mark is affected by nutrition, environment and physical quality. When the digestion and absorption function is not good, the half-moon mark will be blurred, reduced or even disappear. The less the half-moon mark, the worse the energy, the colder the body, that is, the weak immunity, the body hands and feet cold. Usually pay attention to the protection of the nails, supplemental nutrition, enhance the body’s immunity, in order to make the nail moon white normal.