Thrombosis refers to a special structure of blood clots formed by the coagulation of blood flowing in blood vessels. Thrombotic diseases involve multiple organ systems and are a systemic disease. How is blood clot formed? What are the hazards? According to experts, blood clots are mainly divided into the following types based on their location of formation: venous thrombotic diseases, venous thromboembolism, including lower limb deep vein thrombosis and pulmonary embolism. Arterial thrombotic diseases mainly include acute coronary syndrome, atrial fibrillation, arterial ischemia, and stroke. Capillary thrombosis, also known as capillary aneurysm, is more common in the face. Li Wei, Chief Physician of the Department of Vascular Surgery at Peking University People's Hospital: The three elements of thrombosis are mainly when there is damage to the blood vessel wall, such as trauma, inflammation, or slow blood flow, prolonged standing and sitting, or bedridden patients after surgery. Another factor is the hypercoagulable state of the blood, due to medication or taking some hormones; Cancer, tumors, smoking, obesity, and other factors can all cause blood to become hypercoagulable. After these factors are combined, it is more likely to cause thrombosis problems. Experts point out that thrombotic diseases often endanger life, and once suspected of forming a blood clot, immediate medical attention should be sought. Zhang Tao, Chief Physician of Vascular Surgery at Peking University People's Hospital: Once a thrombus is formed, if not treated properly, it will gradually increase and spread, even from calf thrombosis to thigh thrombosis and pulmonary embolism. In severe cases, it can lead to disability and death, so it must be taken seriously, especially the prevention of thrombosis is very important. Experts suggest that to prevent blood clots, one should eat more fresh fruits and vegetables, control meat and oil intake, and maintain appropriate exercise and water intake. Li Wei, Chief Physician of the Department of Vascular Surgery at Peking University People's Hospital: The most crucial point in preventing blood clots is to be active, especially when sitting or standing for a long time. It is necessary to engage in physical activity and lower limb exercises every 30 to 60 minutes to promote blood flow and accelerate blood flow through muscle contraction. It is generally recommended to drink 1500 to 2000 milliliters of water per day. (New Society)