Potassium
Major mineralsYour intake
What each level of potassium does
Approximate dose-response bands. Individual response varies — these are starting points, not prescriptions.
- Severely lowYOU ARE HERE0 mg – 1551 mg
Well below target. Risk of deficiency symptoms tied to electrolyte · bp.
- Insufficient1551 mg – 4700 mg
Below the recommended daily target. Long-term adequacy not assured.
- Adequate4700 mg – 7050 mg
Daily target met. Standard nutritional support for electrolyte · bp.
- Therapeutic7050 mg – 9400 mg
Common for specific health goals. Check the evidence for your situation before sustaining this level.
- Diminishing returns9400 mg – +
Past the point where extra intake typically helps. Evidence for further benefit is thin.
Overview
Principal intracellular cation. Maintains resting membrane potential of all cells and is centrally regulated by Na/K ATPase. Average US intake is roughly half the AI (4,700 mg/day) — the deficit drives blood pressure and cardiovascular risk far more than 'too much sodium' alone.
Functions
- ●Maintains resting membrane potential (every cell)
- ●Required for cardiac and skeletal muscle contraction
- ●Counterbalances sodium for blood pressure regulation
- ●Regulates fluid balance, gastric secretion, and renin-angiotensin tone
- ●Activates many enzymes including pyruvate kinase
Mechanism
Na/K ATPase pumps K+ into cells and Na+ out, creating the gradient that supports nerve conduction, muscle contraction, and secondary active transport. Renal handling is regulated by aldosterone and plasma K+ feedback. Higher dietary K shifts urinary sodium clearance and lowers blood pressure independently of sodium reduction (DASH-Sodium trial).
Benefits
- ●Lowers blood pressure (especially when paired with sodium reduction — DASH)
- ●Reduces stroke risk in cohort studies (~24% per 1,640 mg/day increment)
- ●Reduces kidney stone formation (citrate effect)
- ●Preserves bone mineral density (buffers acid load)
Deficiency
Frank hypokalemia is usually drug-induced (diuretics) or GI loss (vomiting, diarrhea). Inadequate intake (under-AI) is widespread and drives blood pressure, even when serum K is normal.
- ●Muscle weakness, cramps, fatigue
- ●Constipation, ileus
- ●Cardiac arrhythmias, palpitations
- ●Glucose intolerance
- ●Polyuria, polydipsia
- ●Loop and thiazide diuretic users
- ●Chronic vomiting or diarrhea
- ●Chronic alcohol use
- ●Eating disorders, refeeding
- ●Hyperaldosteronism
Excess
Hyperkalemia is the main risk; kidneys excrete excess in healthy adults, but renal impairment, ACE inhibitors, ARBs, K-sparing diuretics, and aldosterone antagonists raise the danger. Cardiac arrhythmias are the proximate concern.
- ●Muscle weakness, paresthesias
- ●Cardiac arrhythmias (peaked T waves on ECG)
- ●Cardiac arrest at severe levels
- ●Often asymptomatic until critical
Forms
- Potassium chlorideStandard supplement and salt-substitute; the clinical workhorse
- Potassium citrate / bicarbonateAlkalinising; preferred for stones and bone-acid load
- Potassium gluconate / aspartateLow-dose OTC; the 99 mg cap is regulatory, not pharmacological
- Food potassiumWhole-food sources are the practical and safest route to adequacy
Food sources
- Baked potato (with skin) · 1 medium925 mg
- Cooked salmon · 3 oz535 mg
- Banana · 1 medium420 mg
- White beans (cooked) · 1/2 cup600 mg
- Cooked spinach · 1 cup840 mg
- Avocado · 1 medium700 mg
Supplement forms
Increase food intake first — DASH-style eating (vegetables, fruits, beans, dairy) routinely doubles potassium without supplement risk. If a clinician prescribes potassium chloride or citrate, follow their dosing closely; potassium supplementation can cause arrhythmias in renal-impaired patients.
Bioavailability
Absorbed throughout the small intestine; ~85% bioavailable from food. OTC supplements are capped at 99 mg per dose by the FDA to prevent GI ulceration; clinical doses use prescription extended-release or liquid forms.
Longevity relevance
Among the strongest dietary signals in cardiovascular epidemiology — higher dietary potassium tracks with lower stroke and all-cause mortality. The DASH dietary pattern (high K, high Ca, high Mg, lower Na, lower saturated fat) consistently outperforms sodium reduction alone for blood pressure control.
Relationships
- Magnesium · Required for Na/K ATPase; hypomagnesemia causes refractory hypokalemia
- Calcium · Together drive the DASH blood-pressure benefit
- Bicarbonate / alkalinising foods · Reduce urinary calcium loss and protect bone
- ACE inhibitors / ARBs · Reduce aldosterone-mediated K excretion; can cause hyperkalemia
- K-sparing diuretics (spironolactone) · Block aldosterone; hyperkalemia risk
- NSAIDs (high dose, chronic) · Reduce renal K excretion
- High sodium intake · Promotes K excretion via tubular exchange
References
About Potassium
Cellular fluid balance, blood pressure regulation, muscle function.
- Role
- Electrolyte · BP
- Daily target
- 4700 mg (DV)
- Also called
- potassium, potassium chloride, potassium citrate, potassium gluconate
The mechanisms and systems this nutrient feeds. Click any to drill into what runs on it.
Top food sources of Potassium
Whole foods that contribute meaningfully (≥10% DV per 100 g serving). Click any food to see its full nutrient profile and what else it brings to the table.