Adult hair yellow may be due to the lack of trace elements, improper care, etc., the solution needs to be dietary conditioning, avoid perm hair, etc.. 1. Lack of trace elements: For adult patients with yellow hair, it may be due to a long-term lack of trace elements, such as lack of iron, zinc and so on. It is easy to cause abnormal function of tyrosinase in the body, leading to the reduction of melanin in the hair and the phenomenon of yellow hair. You can ensure the intake of trace elements through a balanced diet, such as the intake of beef, egg yolks, etc. can supplement iron. Intake of pumpkin seeds, shrimp, pork, etc. can supplement zinc. 2. Improper care: It may be that frequent perming and dyeing of hair, not paying attention to care, etc., will make the hair damaged, resulting in yellow hair. It is recommended to reduce or avoid frequent hair perming and dyeing, regular hair maintenance. If the adult hair yellow is more serious, you need to go to the regular hospital dermatology, clear cause for treatment.