Reasons for frequent swelling of the feet: First, some people stand for a long time because of their work will lead to swelling of the legs, which can subside on its own when lying down. Second, common is kidney disease, because kidney disease will lead to water and sodium retention, hypoproteinemia will cause a decrease in colloid osmotic pressure, which will cause tissue edema. Third, common causes such as heart disease, when there is heart failure, especially right heart failure, will lead to obstruction of venous return and increased venous pressure, which leads to leg edema. Fourth, a common cause is liver disease. Patients with liver disease are often accompanied by hypoproteinemia, which leads to a decrease in plasma colloid osmotic pressure and an increase in interstitial water in tissues, resulting in edema. Fifth, endocrine-related causes, such as hypothyroidism can lead to swelling, and some local factors, such as the formation of venous thrombosis in the legs, can also lead to swelling of the feet.