sodium test checks how much sodium is in the blood. Sodium is
both an electrolyte and mineral. It helps keep the water (the amount of fluid
inside and outside the body's cells) and electrolyte balance of the body.
Sodium is also important in how nerves and muscles work.
the sodium in the body (about 85%) is found in blood and
lymph fluid. Sodium levels in the body are partly
controlled by a
hormone called aldosterone, which is made by the
adrenal glands . Aldosterone levels tell the kidneys
when to hold sodium in the body instead of passing it in the urine. Small amounts of sodium are also lost
through the skin when you sweat.
Most foods have sodium naturally
in them or as an ingredient in cooking. Sodium is found in table salt as sodium
chloride or in baking soda as sodium bicarbonate. Many medicines and other
products also have sodium in them, including laxatives, aspirin, mouthwash, and
Low sodium levels
are uncommon and are most often caused by heart failure, malnutrition, and diarrhea.
such as potassium, calcium, chloride, magnesium, and phosphate, may be checked
in a blood sample at the same time as a blood test for sodium.