Sodium in humans
Sodium is an essential nutrient that regulates blood volume and blood pressure, “maintains the right balance of fluids in the body, transmits nerve impulses, and influences the contraction and relation of muscles”. It is also necessary for maintaining osmotic equilibrium and the acid-base balance. The minimum physiological requirement for sodium is only 500 milligrams per day. However, according to the American Heart Association, in order to “ensure nutrient adequacy and replace sweat losses a healthy adult needs 1,500 milligrams of sodium per day” or 2/3 of a tablespoon.