What does it mean if sodium levels are low in a physical examination?

Low sodium levels in a physical examination refer to a serum sodium concentration below the normal range as detected during routine testing. The normal blood sodium level ranges from 135 to 145 mmol/L; values below this range are considered low.

Sodium is one of the essential electrolytes in the human body and plays a crucial role in maintaining fluid balance, nerve and muscle function, and acid-base balance. Low sodium levels are commonly caused by inadequate dietary intake, gastrointestinal disorders, or cerebral salt-wasting syndrome. Symptoms may include headache, nausea, bradycardia, or tachycardia, and treatment should be symptom-directed. For low sodium due to insufficient dietary intake, it's recommended to improve nutritional intake, drink mildly salted water to supplement sodium appropriately, and for fasting patients, intravenous infusion of sodium chloride injection under medical supervision can help restore sodium levels. In cases of hyponatremia caused by gastrointestinal diseases, symptoms such as nausea and vomiting may occur, and salt capsules may be taken under a physician’s guidance to alleviate low sodium symptoms.

Patients are advised to drink plenty of water, which helps dilute sodium concentration in the blood. At the same time, they should avoid excessively salty foods and increase intake of sodium-containing foods. Appropriate physical activity may also help promote sodium excretion.