Blood viscosity without abnormal biochemical indexes can be improved by lifestyle intervention, and with abnormal biochemical indexes it is recommended to take medication under doctor’s guidance. For people with increased blood viscosity without abnormal biochemical indexes, they should pay attention to the following: hydration, sufficient water can increase the fluid content in the blood and reduce the viscosity; low-salt and low-fat diet, pay attention to vitamin supplementation, and eat more fruits and vegetables; reasonable work and rest, avoiding staying up late; and quitting smoking and limiting alcohol. Those who have abnormal biochemical indicators need to use medication under the guidance of a doctor according to the abnormal situation. For example, patients with hyperlipidemia commonly use statin lipid-lowering drugs (such as simvastatin, atorvastatin, etc.) to lower blood lipids; those with high blood viscosity due to high blood glucose should apply oral hypoglycemic drugs (such as metformin, etc.) or insulin to lower blood glucose, etc., which need to be handled in accordance with the doctor’s instructions.