People often talk about “thick blood”, but today we will talk about it from a medical point of view. The term “blood thickening” is the abbreviation of blood viscosity, and the medical standard name is “hyperviscosity”, which can be detected by blood rheological examination. The main factors affecting blood viscosity are: 1. blood cellular factors, such as the number of blood cells, size, morphology, red blood cell deformability, platelet function, etc. 2. 2, plasma factors, such as plasma proteins (especially fibrinogen, immunoglobulin), blood glucose, lipids, fibrinolytic activity, etc. 3, vascular factors, such as vessel length, diameter and smoothness of the intima, etc. 4, other factors, such as emotions, life style, smoking, alcohol consumption, etc. Any factor that leads to disorders in one or more of the above can cause changes in blood viscosity. For example, if the water in the body of the elderly is relatively reduced, the water content in the blood is also reduced, the ratio of blood cells will be relatively increased, and the viscosity in the blood will be naturally increased. When the plasma proteins such as globulin and fibrinogen are elevated, it will also lead to higher blood viscosity. In hyperlipidemia, the viscosity of blood is also increased. Increased blood viscosity increases the risk of thrombosis, which may lead to myocardial ischemia, cerebral thrombosis, limb vascular thrombosis, and other diseases. Therefore, there are many diseases that can lead to “thickening of the blood”. When talking about “thickening of the blood” alone, it is not yet possible to diagnose the specific disease, but it is necessary to combine other auxiliary tests and medical history to clarify the specific cause. Then, through targeted treatment of the cause, effective measures will be taken, and with effective treatment, the blood viscosity will generally decrease or return to the normal range.