The causes of blood viscosity include: 1. The blood fat is high. Because people usually like to eat greasy and fried food or are overweight, lack of physical exercise, drink less water, and like to smoke and drink a lot, especially patients with diabetes are more likely to have hyperlipidemia and cause blood viscosity. 2. In patients with chronic obstructive pulmonary disease and congenital heart disease, due to ischemia and hypoxia, the body's compensatory production of red blood cells will also cause blood viscosity. 3. For polycythemia vera of blood system diseases, a significant increase in the number of red blood cells in the peripheral blood will also cause blood viscosity. Adjusting the blood viscosity is mainly to change the living habits and eating habits, quit smoking and drinking, eat a light diet, eat less high fat and sugar food, do more aerobic sports, drink more water, control weight, diabetic patients should stabilize the blood sugar level, hyperlipidemia can take lipid lowering drugs to reduce blood lipids.