Swelling of the lower extremities can be classified as physiological or pathological. As we age, the organs in the body become increasingly aged. Physiological swelling occurs due to a decrease in cardiac output and renal blood flow, relaxation of subcutaneous tissues, and a decrease in evaporated water from the skin. Pathological swelling is mostly seen in heart and liver diseases, but also in kidney diseases or malnourished people. Swelling due to chronic right heart failure caused by heart disease, starting from the ankles of both lower extremities and then gradually progressing to the whole body, is mostly seen in coronary heart disease and hypertensive heart disease. When suffering from cirrhosis of the liver, it also starts with swelling of both lower extremities, followed by ascites, and finally progresses to generalized swelling. Swelling caused by kidney disease starts from the eyelids and face, and is mostly seen in pyelonephritis and diabetic nephropathy. There are also many patients with prostate enlargement and bladder tumors who can also develop swelling of the lower extremities. If the heart, liver, and kidneys are fine, it may be a deep vein thrombosis in the lower extremities, and if this is also fine, it is not a big problem. Swelling of the lower extremities is very common in the elderly, so don’t worry too much.