Yellow hair without luster may be related to malnutrition, lack of trace elements, exposure to chemicals or genetic factors. 1. Malnutrition: If the hair is yellow and lusterless, accompanied by dry and thinning hair, the common causes include protein deficiency in nutritional deficiency diseases. In malignant malnutrition, the hair becomes light and brittle, easy to fall off. 2. Lack of trace elements: patients lack of certain trace elements, such as iron, copper, zinc, etc. Copper deficiency will make tyrosinase function is reduced and affect the melanin metabolism. Lack of iron, zinc affects the growth and development of hair cells, making hair yellow and dry. 3. Drugs and chemicals: drugs or other chemicals can also have an impact on the color of hair, such as picric acid can make hair yellow dye. Cosmetic hair coloring is a common cause of hair color change, and hair coloring is often accompanied by hair dryness. The use of too much to oil strong shampoo, alkaline shampoo on the scalp epithelial cells have a strong stimulation, may also lead to hair yellowing, dry. 4. Heredity: If one or both parents have yellow hair without luster, this situation may also occur in the offspring. This is due to genetic factors. If the symptoms of yellowing and lack of luster are serious, or if the symptoms persist and do not improve, you should go to the hospital in time for treatment.