White hair may be caused by genetics, mental factors, or lack of biotin, vitamin B12, folic acid, protein and other nutrients, which can lead to white hair and dryness, easy to break, it is recommended that the hospital nutrition department for examination, to clarify the cause and actively treat the cause. If folic acid deficiency is diagnosed as the cause of gray hair, it can be improved by adjusting the dietary structure and supplementing the nutrients appropriately. Folic acid is a vitamin that is involved in DNA synthesis and cell division, and can be found in a wide range of animal and plant foods. However, the process of food preparation may lead to the destruction of natural folic acid, and the absorption in the intestine may be interfered with by organic acids in mixed foods, so it is possible to cause folic acid deficiency. The synthetic folic acid contained in folic acid tablets is stable and highly absorbed, so you can take folic acid tablets or vitamin B12 tablets to supplement the nutritional elements and relieve gray hair caused by malnutrition, but you should not overdose. Excessive supplementation of folic acid can cause excessive serum synthetic folic acid levels, which affect the efficiency of folic acid receptors on cell membranes, but is not conducive to folic acid absorption. It is usually considered that food and nutrition is an important way to maintain health. You can eat more fruits and vegetables rich in folic acid, such as grapes, pineapple, broccoli, kale, etc., to ensure comprehensive nutrition and thus achieve the prevention of gray hair symptoms. You can assist in using Chinese herbal hair soak and shampoo, or acupuncture and massage scalp techniques to promote the absorption of natural melanin and nutrients in the hair follicles, promote blood circulation, and to a certain extent help black hair grow back.