01/22/2026
The kidneys are like the "precision filters" of the human body, and diabetic nephropathy causes this filter to gradually "fail". The key difference between the two is reflected in their structure, function, and impact on the body:
From a structural perspective, the glomerulus (filter core) of a normal kidney acts like a fine "filter" with uniform pore sizes, allowing only small molecules such as water and metabolic waste to pass through, while large molecules like proteins are blocked. In patients with diabetic nephropathy, the glomeruli become "holey" due to long-term high blood sugar levels. In the early stage, the basement membrane of the filter thickens, the pore size enlarges, and proteins leak into the urine (proteinuria). In the later stage, the glomeruli harden, shrink, and even completely lose their filtering ability.
In terms of function, normal kidneys filter about 180 liters of blood per day, excrete waste products (like urea) accurately, and at the same time retain useful substances like water, proteins, and electrolytes. Additionally, they help regulate blood pressure and produce erythropoietin (which maintains hematopoiesis). In the early stages of diabetic nephropathy, the kidneys become "overloaded" (increased filtration rate) but can no longer prevent protein leakage; in the middle stage, their filtering function declines, leading to the accumulation of waste in the body. In the later stage (kidney failure), the filtering capacity is almost lost, and water and toxins remain, requiring dialysis or a transplant for survival.
Regarding their impact on the body, normal kidneys silently maintain the stability of the internal environment, making it nearly impossible for a person to feel their presence. Diabetic nephropathy can trigger a chain reaction: proteinuria leads to protein loss in the body, resulting in edema and fatigue; the accumulation of toxins causes nausea and skin itching; a decline in erythropoietin leads to anemia; and high blood pressure worsens kidney damage, forming a "vicious cycle".
Simply put, normal kidneys are "efficient gatekeepers", while diabetic nephropathy is a "lost gate" – this damage is reversible in the early stages but becomes harder to reverse in the later stages. Therefore, diabetics should regularly check the protein content in their urine (early signal) and their blood sugar to protect the kidneys, their "lifeline".
