“Table salt, sodium chloride (NaCl), is a naturally occurring mineral essential for animal life. Salt is one of the most widely used and oldest forms of food seasoning (SF Fig. 2.2). Saltiness is one of the five basic human tastes in addition to sweetness, sourness, bitterness, and umami (a savory, meaty taste, such as that of cooked mushrooms, cheese, or soy sauce). As salt dissolves in a solution or on food, it breaks into its component ions: sodium and chloride (Na⁺ and Cl^–, respectively). The salty flavor primarily comes from the sodium ions.

Salt plays a crucial role in maintaining human health. It is the main source of sodium and chloride ions in the human diet. Sodium is essential for nerve and muscle function and is involved in the regulation of fluids in the body.  Sodium also plays a role in the body’s control of blood pressure and volume.

Although sodium is essential, people who consume too much sodium may have hypertension or high blood pressure, a condition that can lead to serious illnesses such as heart disease, kidney disease, and stroke.

Chloride ions serve as important electrolytes by regulating blood pH and pressure. Electrolytes are compounds, often salts, which dissociate into their ionic components in solvents like water. Chloride is also a crucial component in the production of stomach acid (HCl). Humans excrete salt when sweating and must replenish these lost sodium and chloride ions through their diet.”