Fingernail upturning is known as antennal nail, spatulate nail, can be divided into congenital and acquired. Congenital that is inherited from the parents of the anti-nail, can only have a part of the deck deformity or systemic diseases, acquired anti-nail etiology is more, mainly by the organization of iron deficiency or some amino acid metabolism disorders caused by nutritional disorders. Mainly: 1, iron deficiency, normal young children can often see temporary anti-nail, and physiological iron deficiency has an obvious relationship, can eat more iron-rich foods, such as a variety of animal liver to supplement iron. 2, hypoxia, peripheral circulation of blood is not enough, blood oxygen saturation is too low, can cause the local tissue hypoxia metabolic disorders, which leads to anti-nail, highland areas due to the low content of oxygen, suffering from anti-nail of the patient is more, especially in young adults. 3, other, a variety of other reasons can also lead to anti-nail, such as certain fungal infections, trauma, cold, etc., anti-nail can also be a symptom of certain diseases, such as limb atherosclerosis, vitamin deficiency, etc.. As long as the predisposing factors are eliminated, the acquired antennae can subside.