What does aldosterone mean?
Aldosterone is a steroid hormone synthesized by the zona glomerulosa of the adrenal cortex and classified as a mineralocorticoid because of its central role in mineral balance. Its principal job is to signal the kidneys to reabsorb sodium and water while excreting potassium, which directly influences blood volume and blood pressure. Secretion is regulated largely by the renin–angiotensin–aldosterone system, responding to low blood pressure, low sodium, or elevated potassium. Clinically, excess production causes hyperaldosteronism, a treatable cause of hypertension, while deficiency leads to salt wasting and dangerously low blood pressure, as seen in Addison's disease. A family of drugs called aldosterone antagonists, such as spironolactone, block its receptors and are widely prescribed for heart failure and resistant hypertension. Though purely a scientific term, aldosterone is essential vocabulary for anyone reading about blood pressure, kidney function, or hormonal medicine.
nounA steroid hormone produced by the outer layer (cortex) of the adrenal glands that regulates the balance of salt and water in the body, chiefly by promoting sodium retention and potassium excretion in the kidneys.
- (biochemistry, physiology) A mineralocorticoid steroid hormone secreted by the zona glomerulosa of the adrenal cortex that acts on the kidneys to increase sodium reabsorption and potassium excretion, thereby regulating blood pressure and fluid balance.
"The patient's hypertension was traced to abnormally high aldosterone secretion."
"Blood tests showed markedly elevated aldosterone alongside suppressed renin, pointing to primary hyperaldosteronism."
"Spironolactone works as an aldosterone antagonist, blocking the hormone's receptors so the kidneys excrete more sodium and water."
Aldosterone is an uncountable mass noun and has no standard plural form; quantities are expressed with units (e.g. ng/dL) rather than counted instances.
"Serum aldosterone was measured at 25 ng/dL."
Your body produces only a fraction of a milligram of aldosterone a day — yet this tiny hormone can single-handedly send your blood pressure soaring.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of aldosterone
Aldosterone was first isolated in the early 1950s by researchers working on adrenal cortical hormones, following the earlier identification of cortisone and related steroids. Its name combines 'aldo-', referring to the aldehyde group present in the molecule, with '-sterone', the suffix used for ketonic steroid hormones such as testosterone. The word therefore draws on two chemical lineages: the aldehyde nomenclature shared with terms like aldose and acetaldehyde, and the steroid naming tradition rooted in cholesterol-derived compounds. It entered scientific English shortly after its discovery and has remained essentially unchanged since.
How aldosterone is actually used
Strictly a scientific and medical term: aldosterone appears almost exclusively in physiology textbooks, clinical literature, and health journalism, never in casual conversation. It is always written as a singular mass noun. In medical contexts it is frequently discussed as part of the renin–angiotensin–aldosterone system (RAAS), and drugs that block its action are called aldosterone antagonists or mineralocorticoid receptor antagonists.
Easily confused with aldosterone
Cortisol is the adrenal cortex's main glucocorticoid, governing stress responses and metabolism, whereas aldosterone is the main mineralocorticoid, governing salt and water balance.
An aldose is a type of simple sugar bearing an aldehyde group, while aldosterone is a hormone; the shared 'aldo-' prefix reflects chemistry, not function.