Normal kidney function is essential for filtering waste products from the blood, maintaining electrolyte balance, regulating blood pressure, and producing hormones. The kidneys perform these functions by filtering blood through tiny units called nephrons, removing waste products and excess fluids, and returning filtered blood to the circulation. A healthy individual's kidneys filter about 120-150 quarts of blood each day, removing about 2 quarts of waste products and excess water in the urine.
Several factors can affect kidney function, including age, sex, race, and overall health. However, a common measure of kidney function is the glomerular filtration rate (GFR), which measures the rate at which the kidneys filter blood.
- A normal GFR for an adult is 90 to 125 mL/min in individuals older than 2. [31]
- A GFR below 60 may mean kidney disease.
- A GFR of 15 or lower may mean kidney failure.
It's important to note that even with a GFR above 60, a person can have early signs of kidney disease, so regular monitoring is crucial. Doctors use blood tests to measure creatinine levels, a waste product filtered by the kidneys. Elevated creatinine levels may indicate impaired kidney function.
