Aldosterone
What Does Aldosterone Measure?
Aldosterone is a steroid hormone produced by the adrenal glands, specifically in the outer layer called the adrenal cortex. A blood test measuring aldosterone quantifies the concentration of this mineralocorticoid hormone circulating in the bloodstream, typically expressed in nanograms per deciliter (ng/dL) or picograms per milliliter (pg/mL). It can also be measured in urine over a 24-hour collection period to assess daily production.
Why Does Aldosterone Matter?
Aldosterone plays a critical role in regulating blood pressure, sodium and potassium balance, and fluid volume in the body. It signals the kidneys to retain sodium and water while excreting potassium, directly influencing blood pressure and electrolyte homeostasis. Abnormal aldosterone levels are associated with hypertension, adrenal disorders, kidney disease, and electrolyte imbalances such as dangerous drops or spikes in potassium. Testing aldosterone — often alongside renin — is essential for diagnosing conditions like primary hyperaldosteronism (Conn's syndrome) and adrenal insufficiency, both of which can have serious cardiovascular and metabolic consequences if left untreated.
Normal Ranges
Males
Upright: 7–30 ng/dL; Supine: 3–16 ng/dL
Females
Upright: 7–30 ng/dL; Supine: 3–16 ng/dL (levels may be higher during pregnancy)
Children
Varies by age; newborns: up to 500 ng/dL; children 1–3 years: 5–60 ng/dL; older children approach adult ranges
Causes of High Levels
- Primary hyperaldosteronism (Conn's syndrome) — an adrenal tumor or overgrowth causing excess aldosterone production independent of renin
- Secondary hyperaldosteronism — conditions like heart failure, liver cirrhosis, nephrotic syndrome, or renal artery stenosis that trigger elevated renin and subsequently high aldosterone
- Dehydration or low sodium intake — stimulates the renin-angiotensin-aldosterone system (RAAS) to conserve fluid
- Prolonged standing or upright posture — body position can transiently elevate aldosterone levels
- Certain medications — diuretics, oral contraceptives, and laxative overuse can raise aldosterone
- Adrenal hyperplasia — bilateral enlargement of the adrenal glands leading to excess hormone secretion
Causes of Low Levels
- Primary adrenal insufficiency (Addison's disease) — damage to the adrenal cortex reduces aldosterone and cortisol production
- Hypoaldosteronism — a specific deficiency in aldosterone production, often linked to low renin states or enzyme defects
How to Improve Your Aldosterone
Diet
- Moderate sodium intake (1,500–2,300 mg/day) to avoid chronically suppressing or overstimulating aldosterone
- Increase potassium-rich foods such as bananas, sweet potatoes, spinach, and avocados to support electrolyte balance
- Avoid excessive licorice (glycyrrhizin) consumption, which mimics aldosterone and can disrupt hormonal balance
- Stay well hydrated to prevent dehydration-driven spikes in aldosterone
- Reduce processed and packaged foods high in hidden sodium that can dysregulate the RAAS system
Supplements
- Magnesium (200–400 mg/day) — supports adrenal function and electrolyte regulation; consult a doctor before use
- Potassium supplementation (under medical supervision) — may be needed if hypokalemia results from high aldosterone
- Vitamin D (1,000–2,000 IU/day) — has been shown to modulate RAAS activity and may help regulate aldosterone
- Omega-3 fatty acids (1–3 g/day of EPA/DHA) — may help reduce aldosterone-driven inflammation and cardiovascular risk
Related Biomarkers
Frequently Asked Questions
What is the aldosterone-to-renin ratio and why is it important?
The aldosterone-to-renin ratio (ARR) is calculated by dividing the aldosterone level by the renin level. It is the most commonly used screening test for primary hyperaldosteronism (Conn's syndrome). A high ARR — typically above 20–30 ng/dL per ng/mL/hr depending on the lab — suggests aldosterone is being produced autonomously by the adrenal glands rather than in response to renin signals. This ratio helps distinguish primary from secondary causes of high aldosterone.
Can aldosterone levels affect blood pressure?
Yes, aldosterone is one of the key hormones regulating blood pressure. It instructs the kidneys to retain sodium and water, which increases blood volume and raises blood pressure. When aldosterone is chronically elevated — as in primary hyperaldosteronism — it causes resistant or difficult-to-treat hypertension. Studies show that excess aldosterone also directly damages blood vessels and the heart, increasing cardiovascular risk beyond what blood pressure alone would predict.
Does body position affect aldosterone test results?
Yes, significantly. Aldosterone levels are notably higher when a person is standing (upright) compared to lying down (supine). This is because standing reduces blood return to the heart, triggering the RAAS to activate. Labs typically note whether blood was drawn in a supine or upright position, and reference ranges differ accordingly. Patients are often asked to rest in a specific position for 30 minutes before the blood draw to ensure accurate, standardized results.