Aldosterone

Aldosterone is a steroid hormone classified as a mineralocorticoid, produced primarily in the zona glomerulosa of the adrenal cortex. It is the principal hormone responsible for sodium retention and represents one of the body's key stress-adaptive hormones. In excess, aldosterone is increasingly recognized as an "endogenous toxin" that activates numerous inflammatory and degenerative stress reactions throughout the body.

Aldosterone
Abbreviation	ALD, ALDO
Molecular formula	C₂₁H₂₈O₅
Type	Mineralocorticoid steroid hormone
Administration	N/A
Bioavailability	N/A
Synonyms	Aldocorten, Electrocortin, 18-Oxocorticosterone, 18-Aldocorticosterone
Source	Not supplemented - endogenous toxin, produced in the zona glomerulosa (outer layer) of the adrenal cortex.
Ray's verdict	Generally hurts Negative - an "endogenous toxin." Aldosterone and parathyroid hormone interfere with mitochondrial energy production the same way polyunsaturated fats do, intensifying hypothyroidism or glucose deficiency. People are now starting to speak of it as an endogenous toxin that activates so many stress reactions. Serotonin is a major factor in turning it on. Salt intake suppresses aldosterone (increased salt → lower aldosterone). Progesterone protects against aldosterone's harmful effects. New anti-aldosterone drugs for hypertension/heart failure are recognized for their similarity to progesterone.

Aldosterone functions within the broader renin-angiotensin-aldosterone system (RAAS), working alongside angiotensin II as a central mediator of blood pressure, fluid balance, and, unfortunately, chronic inflammation when chronically elevated.

"Aldosterone is part of the renin-angiotensin-aldosterone system, increasing your blood pressure and all of the stress-related, virus-related conditions."

Dosing

Substances that lower aldosterone

Rather than dosing aldosterone itself (which would be harmful), the therapeutic goal is typically to lower aldosterone through:

1. Adequate sodium intake - Increased salt in the diet causes aldosterone to decrease

In a region of Mongolia or northern China where people consume at least 30 grams of salt a day, a physician found no hypertension at all, even among the oldest people.

1. Vitamin D - Maintaining levels of 50-60 ng/mL helps suppress the RAAS system
2. Calcium - Calcium works with vitamin D to hold down your aldosterone
3. Progesterone - Acts as a natural mineralocorticoid antagonist. In Hans Selye's experiments, "progesterone supplement totally replaced all of the adrenal hormones, aldosterone and cortisol in particular" in animals without adrenal glands.
4. Aspirin - "Aspirin, which is antilipolytic, decreasing the release of free fatty acids... lowers the production of stress-induced aldosterone, and helps to lower blood pressure, if it's taken in the evening"
5. Cyproheptadine - Through its anti-serotonin effects, it "can reliably lower aldosterone"

History

Etymology

The name combines "aldehyde" (referring to a distinctive aldehyde group in its structure) with "sterol" and the ketone suffix "-one."

Sylvia Tait, James Tait, and Tadeusz Reichstein isolated aldosterone in 1953, identifying it as the primary mineralocorticoid responsible for sodium retention, distinct from the glucocorticoid cortisol.

The name aldosterone derives from its chemical structure: "aldo-" refers to the aldehyde group at the C18 position of the molecule, while "-sterone" indicates its steroid nature. The hormone was identified and characterized in the mid-20th century, after progesterone's role in regulating salts, water, and energy metabolism was already well established.

"Even before aldosterone was identified, progesterone's role in regulating the salts, water, and energy metabolism was known, and after the functions of aldosterone were identified, progesterone was found to protect against its harmful effects."

Structure/Chemical properties

Aldosterone is a C21 steroid hormone (21 carbon atoms) belonging to the mineralocorticoid class. Structurally, it contains:

• A characteristic aldehyde group at the C18 position (distinguishing it from other corticosteroids)
• A hydroxyl group at C11
• A ketone group at C3
• An unsaturated A-ring

Aldosterone is relatively hydrophilic compared to steroids like pregnenolone, progesterone, and DHEA. This affects its cellular uptake. Hydrophilic steroids like aldosterone and cortisol are less preferentially accumulated inside cells compared to more lipophilic steroids.

Aldosterone shares structural similarity with progesterone, which explains why progesterone acts as a natural aldosterone antagonist at the mineralocorticoid receptor. Synthetic aldosterone antagonists like spironolactone are essentially modified versions of the progesterone molecule. Spironolactone is "basically a diuretic, it's a mineralocorticoid receptor antagonist... progesterone is the same - actually progesterone has a higher affinity for the MR receptor than spironolactone."

Function/Mechanism of Action

Primary functions

Aldosterone's central regulatory function is sodium retention. When the body perceives sodium deficiency, low blood volume, or hypoglycemia, aldosterone is secreted to retain sodium in the kidneys, colon, sweat glands, and salivary glands.

"Aldosterone has the central function of making you not lose sodium so fast. Keeping the sodium inside your bloodstream helps the blood to absorb water so that it doesn't form edema."

However, this comes with significant trade-offs. The side effects of aldosterone include:

• Loss of potassium and magnesium - "Instead of losing sodium, you lose potassium and magnesium, and the loss of potassium and magnesium are very important in causing heart rhythm problems."
• Increased vascular permeability through VEGF (vascular endothelial growth factor)
• Inflammation and fibrosis in multiple organ systems

Triggers for aldosterone release

Several conditions stimulate aldosterone production:

1. Low sodium intake - "A restriction of salt in the diet causes more aldosterone to be produced"
2. Hypoglycemia - "Low blood sugar is enough to start the process signaling your kidneys to send out renin and starting the process to produce aldosterone"
3. Reduced blood volume - From dehydration, hyperventilation, or protein deficiency
4. Polyunsaturated fatty acids - "Arachidonic acid, even without being converted to prostaglandins, is an important activator of aldosterone synthesis"
5. Serotonin - Acts as a major stimulator of aldosterone release

Low blood sugar alone can signal the kidneys to release renin and start aldosterone production; too little salt and loss of blood volume from leaky vessels, for example with hyperventilation, also raise it. Any stress that increases aldosterone makes cells lose magnesium; keeping aldosterone and inflammation down and thyroid, calcium and sodium up helps retain it. Progesterone prevents the toxic effects of excess aldosterone and cortisol.

Effects on mitochondrial energy production

One of aldosterone's most concerning effects is its direct interference with cellular energy production.

"Aldosterone and parathyroid hormones interfere with mitochondrial energy production the same way polyunsaturated fats do, intensifying the problem of hypothyroidism or glucose deficiency."

— Ray Peat

This mitochondrial-blocking effect explains aldosterone's connection to numerous degenerative conditions. "The aldosterone directly blocks your mitochondrial energy production and increases the parathyroid hormone activity, which itself functions by blocking your mitochondrial oxidation and making up for it with glycolytic energy production, which shifts you over into the reductive stress, the failure of oxidation."

Relationship with other hormones

Aldosterone works synergistically with other stress hormones:

• Parathyroid hormone (PTH) - Both block mitochondrial respiration and promote lactic acid production
• Cortisol - Shares similar effects through glucocorticoid and mineralocorticoid receptor crosstalk
• Estrogen - Increases aldosterone production; "Estrogen is also increased in pattern baldness, also appears to increase aldosterone" (Danny Roddy, "Male Pattern Baldness Myth")
• Prolactin - "All three hormones - estrogen, prolactin, and aldosterone - appear to work together to waste salt in the urine but retain it in the tissues" (Danny Roddy, "Male Pattern Baldness Myth")

Medical uses/Effects

Conditions where aldosterone is elevated

Elevated aldosterone (hyperaldosteronism) is associated with:

• Hypertension
• Heart failure
• Pattern hair loss - Elevated levels of aldosterone are seen in men and women with pattern baldness
• Depression - "The use of bright light (which suppresses melatonin) to treat depression probably helps to inhibit the production of aldosterone, which is strongly associated with depression"
• Kidney disease
• Increased cancer risk - Chronic hyperaldosteronism has been associated with an increased cancer risk

Aldosterone antagonists as treatment

Aldosterone antagonists have become recognized therapies for multiple conditions. "Aldosterone antagonists are now being recognized as effective treatments for hypertension, water retention, congestive heart failure, arrhythmia, diabetes, kidney disease, and a great variety of inflammatory problems."

Pharmaceutical options include:

• Spironolactone - A synthetic progesterone derivative
• Eplerenone - A more selective mineralocorticoid antagonist

Natural antagonists include:

• Progesterone - "Synthetic drugs to antagonize aldosterone are most effective when they are most like natural progesterone... progesterone, the 'antifibromatogenic steroid,' should be helpful for those problems that have been considered irreversible."
• Pregnenolone - "Pregnenolone (just like progesterone) is a potent aldosterone antagonist in low nanomolar concentrations"

Anti-fibrotic effects of aldosterone reduction

Since aldosterone promotes fibrosis, its antagonism helps prevent and potentially reverse fibrotic changes: "Besides inflammation, aldosterone leads to fibrosis and prolonged heart failure and vascular and kidney disease and so on that lead to fibrosis, lung disease. Everywhere that water retention and inflammation start, they tend to end up with fibrosis."

Side/Adverse effects

Effects of aldosterone excess

Chronic elevation of aldosterone produces numerous harmful effects:

Cardiovascular:

• Hypertension
• Heart failure - "Aldosterone is widely recognized as one of the primary contributors to heart failure" (Georgi Dinkov, Generative Energy podcast #22)
• Vascular calcification
• Increased blood vessel permeability

Metabolic:

• Insulin resistance - "Aldosterone secretion increases during the night... it inhibits energy metabolism, increases insulin resistance"
• Contribution to diabetes - "Aldosterone appears to contribute to the hyperglycemia of diabetes itself, and not just to its complications, by interfering with the interactions of insulin and cortisol"

Mineral Imbalances:

• Potassium depletion
• Magnesium depletion - Contributing to vasoconstriction, inflammation, and bone loss
• Paradoxical intracellular sodium accumulation despite sodium retention

Tissue Degeneration:

• Fibrosis of heart, kidneys, lungs, liver
• Tissue "brittleizing" - Ray called it the major brittleizing hormone

Other Effects:

• Stimulation of cell division through polyamine production
• Nocturnal stress - Aldosterone rises during the night, contributing to catabolic processes and poor sleep
• Bone loss - Works synergistically with parathyroid hormone to promote osteoporosis

The nocturnal rise

Aldosterone naturally rises during the night, which is problematic: During aging, salt restriction can produce an exaggerated nocturnal rise in aldosterone. This nocturnal elevation contributes to the fact that night and winter are where most aging degeneration takes place.

Protective measures before bed include salty soup or milk to suppress the nocturnal rise of aldosterone and other stress hormones.

Renin–angiotensin

Angiotensin II is a vessel-constricting peptide in the renin-aldosterone axis. It raises pressure and aldosterone.

History (Angiotensin)

Etymology (Angiotensin)

The name combines Greek angeion ("vessel") with "tension," describing its effect of raising blood pressure by constricting blood vessels.

Two research groups discovered the compound independently in the late 1930s, one in Argentina naming it "hypertensin" and one in the United States naming it "angiotonin." The two names were merged into "angiotensin" in 1958 once the groups confirmed they had found the same substance.

Angiotensin was independently discovered by two research groups in the late 1930s and early 1940s, one in Argentina (Braun-Menendez) and one in the United States (Page and Helmer), who each identified a pressor substance generated when renin acted on a plasma protein. The two groups originally used different names for their finding, "angiotonin" and "hypertensin", before agreeing in 1958 to the combined name "angiotensin" that's used today.

Structure/Chemical properties (Angiotensin)

Angiotensin II is an octapeptide (eight amino acids). It's produced from angiotensinogen, a liver-made plasma protein, in two cleavage steps: renin first cuts angiotensinogen down to the decapeptide angiotensin I, then angiotensin-converting enzyme (ACE), concentrated in lung capillaries, removes two more amino acids to yield the active octapeptide, angiotensin II.

Function/Mechanism of Action (Angiotensin)

Angiotensin II acts through AT1 receptors on blood vessel walls to cause vasoconstriction, directly raising blood pressure. It also stimulates the adrenal cortex to release aldosterone, which promotes sodium retention, further supporting blood pressure and volume. Reduced kidney blood flow, most often from low sodium intake or reduced blood volume, triggers the kidney to release renin, starting the whole cascade.

It has been known for many years that decreasing sodium intake causes the body to respond adaptively, increasing the renin-angiotensin-aldosterone system (RAAS). The activation of this system is recognized as a factor in hypertension, kidney disease, heart failure, fibrosis of the heart, and other problems.

— Ray Peat

Clinical significance

Angiotensin II itself is used clinically as an IV drug (brand name Giapreza) to raise blood pressure in severe, treatment-resistant shock. The pivotal trial (344 patients with vasodilatory shock unresponsive to high-dose vasopressors) found 69.9% of the angiotensin II group reached target blood pressure at 3 hours versus 23.4% on placebo, though 28-day mortality was not significantly different (46% vs 54%). Far more common in practice is targeting the system pharmaceutically from the other direction: ACE inhibitors and angiotensin receptor blockers (ARBs) are among the most widely prescribed blood-pressure drugs, working by blocking angiotensin II's formation or action. In the bioenergetic framework, chronic RAAS activation is viewed less as a target for lifelong drug suppression and more as a downstream response to inadequate salt intake or reduced effective blood volume, addressing the salt/volume driver is favored over indefinitely blocking the resulting hormone cascade.

Renin is released by the kidney to start the angiotensin-aldosterone cascade when pressure or salt sensing falls. High renin states track stress and low effective volume.

History (Renin)

Etymology (Renin)

The name comes from Latin ren ("kidney"), the organ that secretes it.

Robert Tigerstedt and Per Bergman discovered renin in 1898, showing that kidney extracts could raise blood pressure, decades before its role in the renin-angiotensin-aldosterone system was worked out.

Renin was discovered in 1898 by Robert Tigerstedt and his student Per Bergman, who found that extracts of rabbit kidney tissue, when injected into other rabbits, raised blood pressure. They named the substance "renin" after the Latin ren (kidney). Its role as an enzyme that acts on a separate plasma substrate, rather than as a pressor hormone itself, wasn't clarified until decades later.

Structure/Chemical properties (Renin)

Renin is an aspartyl protease, an enzyme of roughly 340 amino acids (about 37 kDa) that is synthesized as an inactive precursor (prorenin) and stored in secretory granules in kidney juxtaglomerular cells before being cleaved to its active form and released into circulation.

Function/Mechanism of Action (Renin)

Renin's only known substrate is angiotensinogen, the liver-made plasma protein it cleaves to form angiotensin I, the first step of the renin-angiotensin-aldosterone system (RAAS). Renin release is triggered by reduced kidney blood flow, low sodium delivery to the kidney's distal tubule, and sympathetic nervous system activity, conditions commonly produced by a low-salt diet or reduced blood volume.

During pregnancy, the reduced blood volume doesn't adequately nourish and oxygenate the growing fetus, and the reduced circulation to the kidneys causes them to release a signal substance (renin) that causes the blood to circulate faster, under greater pressure.

— Ray Peat

Clinical significance (renin–angiotensin)

Plasma renin activity is measured clinically to help classify hypertension (low-renin vs. high-renin forms) and to guide use of RAAS-targeting drugs. Renin itself is not administered as a drug; instead, drugs target it indirectly (ACE inhibitors, ARBs) or directly inhibit it (aliskiren). In the bioenergetic framework, chronically elevated renin from inadequate dietary salt is treated as a correctable driver, part of why salt restriction is viewed skeptically here even though it does lower measured blood pressure numbers in the short term.