To turn gray hair black, we must first consider the cause of the gray hair and the age of the patient so that we can choose an effective treatment. If the patient is younger and has a small amount of gray hair, it may be related to micronutrient deficiency, and it is recommended to eat more iron-rich vegetables, such as spinach and celery, and to get enough sleep, which may have some curative effect. If the patient is older, in Chinese medicine, it is considered to be related to liver and kidney deficiency, consider the treatment method of tonifying liver and kidney, such as taking Six Flavored Dihuang Pills orally and washing hair with ginger and other herbs externally, the efficacy is not sure. Diet can eat more black food, such as wood fungus, black beans, etc., can also make the hair darker to increase the luster.