Now, shall we look into this phenomenon through the precise science of our body? Body fluids in Donguibogam is very similar to the modern medical concept encompassing all fluids that make up our body, such as plasma in the blood, interstitial fluid between cells, lymph, and intracellular fluid inside cells. These body fluids are fundamental conditions for life, transporting nutrients and oxygen, eliminating wastes, and participating in thermoregulation and immunity. And the command center that delicately regulates the balance of all these body fluids is the kidney. The kidneys go beyond simply making urine; they simultaneously act as our body's water purifier and chemical plant. They filter about 180 liters of blood per day, reabsorbing necessary substances and excreting unnecessary wastes and excess water as urine.
What happens when kidney hypofunction occurs? First and foremost, fluid and electrolyte imbalance develops. As the kidneys' ability to concentrate urine declines, body water is excessively lost through urine. A vicious cycle occurs where no matter how much water you drink, you quickly go to the bathroom and feel thirsty again. This happens because the regulatory function of antidiuretic hormone (ADH) is also impaired, preventing the body from effectively preserving water. At the same time, the balance of essential electrolytes such as sodium, potassium, and calcium is disrupted, which can cause serious problems such as muscle weakness and abnormal heartbeat.
Furthermore, the kidneys play a key role in blood pressure regulation. They maintain stable blood pressure through a complex mechanism called the renin-angiotensin-aldosterone system (RAAS), and when kidney function declines, this regulatory capacity is lost, easily leading to hypertension. When the ability to excrete wastes drops and uremic toxins accumulate in the body, symptoms such as whole-body fatigue, loss of appetite, and nausea appear, and in severe cases, brain function can also be affected.
Chronic fatigue often occurs because the secretion of erythropoietin, a hormone through which the kidneys assist erythropoiesis, decreases, leading to anemia. Swelling, or edema, is a phenomenon that occurs when the kidneys fail to properly excrete salt and water, accumulating them in the body. It commonly appears in the legs, ankles, or around the eyes. In this way, kidney hypofunction goes beyond a simple problem of water management; like dominoes, it affects every system in our body, from blood pressure, blood production, and bone health to systemic metabolism. In early stages, symptoms are vague and difficult to notice, but if left untreated, it can progress to chronic kidney disease (CKD), reaching a serious situation where dialysis or kidney transplantation must be considered. Therefore, we must listen to our body and not miss even minor signals.
