Curly hair is caused by congenital factors or acquired factors. 1. Congenital factors: congenital factors are mainly due to genetic factors, if there are elders in the family who have curly hair, then there is a high probability that the next generation will also have curly hair. 2. Acquired factors: when the body lacks copper elements, metabolic disorders and hair after physical perm hair coloring, hair will appear curved phenomenon. Note that congenital factors lead to hair curvature can not be changed, can be straightened, but only temporary; and acquired factors lead to hair curvature can pay attention to hair care in normal times, choose some mild shampoo and conditioner, the use of hair dryers do not temperature is too high and try to minimize the perm and dyeing of hair, reduce hair damage. It is recommended to eat more food rich in high quality protein, timely replenishment of the body’s nutrients, to ensure balanced nutrition, can promote better hair growth.