Vitamin B12 does not fight fatty liver. Fatty liver is a chronic liver disease caused by poor lifestyle. Long term treatment is required in case of fatty liver. For severe obesity, weight loss medications such as orlistat may be given. Patients with combined hyperlipidemia can be given beta or statin medications such as fenofibrate, atorvastatin, simvastatin, and so on. Vitamin B12, also called cobalamin, is the only vitamin that contains the metal element. Vitamin B12 can be used in the treatment of megaloblastic anemia, but does not have efficacy in treating fatty liver and cannot be used as a substitute for related medications. Vitamin B12 can have adverse effects such as hypokalemia and hyperuricemia. Neurological damage, before the diagnosis is not clear, should not apply vitamin B12, so as not to mask the clinical manifestations of subacute joint degeneration. Patients with fatty liver, should take the relevant drugs under the guidance of a doctor, please do not take the drug on their own, so as not to delay the condition.