According to Chinese medicine, this change in the nails is closely related to the low function of the body’s tissues and organs, the destruction of tissue structure, atrophy and other pathological changes. Diabetic, immunocompromised, malnourished, and elderly groups are the most prevalent groups of nail fungus; young women with nail care habits are susceptible. Nail fungus usually has no conscious symptoms, but when combined with nail fungus, pain and itching can occur. The nail may change in color, shape and texture. The nail may become thick, deformed, small concave, and lose its luster, and sometimes it may become “hook” or “trumpet” shaped. The most common color is grayish yellow, which is also the origin of “gray nail”, and it can also be yellow, red, white, green, etc. In addition to the cosmetic effects, nail fungus can also cause discomfort at the ends of the fingers and toes. When the body’s resistance is low, it can often invade the nail and the surrounding tissue, forming damage to the fingers and toes, and in serious cases can be a source of infection spread to the whole body. Vertical lines: The surface of the nail is not smooth enough and a straight line appears, usually after overexertion or overuse of the brain; these lines will be clearly visible when there is a lack of sleep. If the vertical lines persist, it may be a chronic pathology of the internal organs. If not taken care of, the nails will become uneven and even crack as the condition progresses. Horizontal lines: The horizontal lines on the nails are a record of a lesion that has already occurred. In other words, when horizontal lines appear on the nails, some lesion must have already occurred in the body. Generally, the horizontal lines start at the very bottom of the nail and gradually move upward as the nail grows, signaling that the onset of the disease is getting closer. Spots: A small amount of white spots on the nails is usually a sign of calcium deficiency, silicon deficiency or parasitic disease; a larger number of white spots may be a sign of neurasthenia; and yellow dots on the nails may be suffering from digestive system diseases; if black spots appear on the nails be careful, the lighter is just overworked, malnutrition, the heavier may be a precursor of gastric prolapse, stomach cancer, uterine cancer.