Sodium

Also known as salt, sodium chloride, electrolyte, electrolytes.

Last reviewed October 9, 2026 · Jump to references

What is Sodium?

In plain words

Sodium is a mineral that helps balance body fluids and keeps nerves and muscles working; table salt contains sodium and chloride. The kidneys control how much sodium stays in the body and remove excess in urine. Researchers study its effects on blood pressure, hydration, and heart health. Too much sodium can raise blood pressure, and very low or very high sodium levels in the blood can be dangerous.

Technical definition

Sodium is a chemical element present in the body as the monovalent cation Na+, the principal extracellular electrolyte; sodium chloride is a salt containing sodium and chloride, not a synonym for sodium itself. Sodium movement through ion channels and transporters, including gradients maintained by the Na+/K+-ATPase pump, supports fluid balance, nerve signaling, muscle contraction, and nutrient transport. Sodium is an essential nutrient found in foods and dietary supplements, while sodium-containing medicines are regulated according to their formulation and intended use.

Educational information only. This page does not provide medical advice or determine whether a supplement is appropriate for you. Review supplements with a qualified healthcare professional, especially if you take medication, are pregnant, have surgery scheduled, or have a chronic medical condition.

Evidence by use

Each use is rated on its own. There is no single overall effectiveness score.