The specific gravity of urine (SG) is a measure of the density of urine relative to pure water. It is used to evaluate how well the kidneys are diluting the urine. A normal SG of urine ranges from 1.002 to 1.030. Urine with a higher SG is more concentrated, while urine with a lower SG is more dilute.
The specific gravity of urine is determined by comparing the density of urine to the density of water. The SG of urine is usually measured with a handheld refractometer or a urinometer, which is a device that measures the density of a liquid. Urine SG is affected by the amount of waste products and other substances in the urine, such as proteins, glucose, ketones, and red blood cells.
The SG of urine can be used to help diagnose certain medical conditions, such as kidney disease, diabetes, and urinary tract infections. A low SG can indicate that the kidneys are not adequately diluting the urine, which can be a sign of kidney disease. A high SG can indicate that the kidneys are not removing enough waste products from the body, which can be a sign of diabetes or dehydration.
The SG of urine can also be used to help monitor the effectiveness of certain medications, such as diuretics. Diuretics are medications that help the body get rid of excess fluid. By measuring the SG of urine before and after taking a diuretic, a doctor can determine if the medication is working as expected.
The specific gravity of urine is a useful tool for diagnosing and monitoring certain medical conditions. It is important to keep in mind that the SG of urine can be affected by many factors, such as diet, hydration, and medications. Therefore, it is important to discuss any changes in the SG of urine with a doctor to determine the underlying cause.