Nails without crescent does not necessarily have a disease, because nails without crescent is genetically determined. First of all, some people due to genetic reasons, methyl more backward nail growth is slower, so the phenomenon of missing crescent moon is not caused by physical health conditions, but the performance of genetic symptoms. So no crescent is not a disease, just a very normal performance, just as the length of each finger. Secondly, the number of fingernail crescent and the growth rate, some people have strong metabolism, nail keratinocyte synthesis faster, so the crescent will be more, and some people’s metabolism is slow, the corresponding number of crescent is less, the crescent is smaller, but the strength of the metabolism in fact, in addition to the health status of the body is related to the seasons may be related to the human body, for example, the function in the summer will be more vigorous, metabolism fast, while the winter is slower, so the crescent is not a disease, just as fingers have their own length. For example, in summer, the human body functions more vigorously, the metabolism is fast, and in winter, it is slower, so the number of crescent moon will be less. Therefore, there is no correlation between the presence or absence of crescent moon and the presence or absence of disease.