Sodium is an essential electrolyte found in the blood that helps regulate fluid balance in the body and plays a critical role in nerve and muscle function. A blood test for sodium levels can provide important information about a person's overall health and help diagnose conditions such as dehydration, kidney disease, and heart failure. Normal sodium levels in the blood range from 135 to 145 milliequivalents per liter (mEq/L). Abnormal levels can indicate an underlying health problem and may require further medical evaluation. Our blood test for sodium is a simple and accurate way to monitor this important electrolyte and ensure optimal health.