It is a natural phenomenon in the process of nail growth. The absence of nail crescent is mainly considered to be related to physiological factors. Physiological factors are related to the individual’s physical condition, nutritional status, nail growth rate, etc. The number and size of the nail halves may vary due to individual differences in growth and development. If there are no symptoms, there is no need to worry. In addition, do not rule out pathological factors, common in the following cases: 1, nutritional deficiencies: nails without crescent may be related to nutritional deficiencies, such as long-term nutritional intake, making vitamin, trace element deficiencies, will not only lead to anemia symptoms, may also lead to nail whitening, nail crescent disappearance and other symptoms, such cases should pay attention to the body, observe whether it will be accompanied by dizziness and other symptoms. 2, gastrointestinal malabsorption: this condition is common in people suffering from diarrhea, indigestion and other diseases, feces attached to the intestinal wall, resulting in poor absorption rate, while affecting the growth of the nail crescent; 3, slow metabolism: some people have a fast metabolism, the nail can grow quickly, but the blood vessels under the nail is not fully formed, that is, the formation of the nail crescent, while for the elderly and children, the nail and blood vessel growth rate 4, local infection: such as nail infection, usually due to minor trauma secondary to bacterial infection, due to perinail tissue redness, swelling, abscess, resulting in the disappearance of nail crescent; 5, systemic diseases: nails without crescent may also indicate the body pathology, such as renal insufficiency, nerve damage, etc., but also may be due to thyroid disease, neurasthenia, anemia, etc. It can also be caused by thyroid disease, neurasthenia, anemia and other factors. In addition, a small number of people may also suffer from irregularities in their lives and mental stress, which may lead to the absence of a crescent under the nail. If you find no crescent on your fingernails, first of all, you should pay attention to whether there are any other discomforting symptoms in your body. If there are symptoms such as loss of appetite and dizziness, you should actively go to the hospital for examination and diagnosis, and carry out targeted treatment. Secondly, we should pay attention to a reasonable diet structure in daily life, choose nutritious food and fresh vegetables and fruits, such as eggs, fish, green leafy vegetables, etc., and exercise appropriately, choose aerobic exercises suitable for you, such as swimming, jogging, etc., which can contribute to physical health.