Sodium is an essential mineral and electrolyte that plays a critical role in maintaining fluid balance, nerve function, and muscle activity. Most sodium in the body comes from dietary intake, and excess sodium is excreted through urine by the kidneys. Urinary sodium levels reflect both dietary sodium consumption and how effectively the kidneys are regulating sodium balance.
Measuring sodium in urine helps assess hydration, kidney function, and sodium-related health conditions, such as high blood pressure, electrolyte imbalances, or dehydration.