Evidence Level
Very Strong
1 Clinical Trial
4 Documented Benefits
5/5 Evidence Score

Potassium is the most abundant intracellular cation in the human body, critical for maintaining membrane potential, regulating fluid balance, and supporting cardiovascular and skeletal muscle function. Most adults are chronically under-consuming potassium, increasing risk of hypertension, kidney stones, and muscle cramps.

Studied Dose 4,700 mg/day Adequate Intake; supplements typically 99–300 mg/serving due to FDA label limits
Active Compound Potassium citrate / Potassium chloride / Potassium gluconate

Blood pressure reduction

Potassium counteracts the blood pressure-raising effects of sodium by promoting renal sodium excretion and relaxing blood vessel walls. Every 1 g/day increase in potassium intake is associated with ~1–2 mmHg reduction in systolic BP.

Cardiovascular health

Higher dietary potassium intakes are strongly associated with reduced risk of stroke, heart disease, and arrhythmia. Adequate potassium maintains cardiac muscle electrical potential and prevents dangerous rhythm disturbances.

Muscle function and cramp prevention

Potassium is essential for muscle membrane repolarization after contraction. Deficiency causes muscle weakness, cramps, and fatigue — particularly common in athletes with high sweat losses.

Kidney stone prevention

Potassium citrate alkalinizes urine and reduces calcium excretion, significantly reducing risk of calcium oxalate kidney stone formation. Clinically used as pharmaceutical treatment for recurrent nephrolithiasis.

1

Sodium-potassium ATPase pump

Na+/K+-ATPase pumps maintain the steep potassium gradient across cell membranes, which is the foundation of the resting membrane potential in all excitable cells (neurons, cardiac, skeletal muscle).

2

Renal natriuresis

High potassium intake stimulates aldosterone-independent renal sodium excretion, directly lowering blood volume and blood pressure. This mechanism explains potassium's antihypertensive effect.

3

Vascular smooth muscle relaxation

Potassium activates membrane hyperpolarization in vascular smooth muscle cells via K+ channel opening, causing vasodilation and reduced peripheral resistance.

1
Potassium Supplementation and Blood Pressure — Meta-Analysis
PubMed

Cochrane meta-analysis of 22 RCTs examining potassium supplementation effects on blood pressure.

1,606 participants across 22 RCTs.

Potassium supplementation reduced systolic BP by 3.5 mmHg and diastolic BP by 2.0 mmHg. Larger effects in hypertensive individuals and those with high sodium intake.

Common Potential side effects

GI discomfort, nausea, and diarrhea with high-dose supplements — take with food
Hyperkalemia (elevated blood potassium) in those with kidney disease or on K-sparing diuretics
Potassium chloride has unpleasant bitter taste — citrate or gluconate forms better tolerated

Important Drug interactions

ACE inhibitors and ARBs — increase potassium retention; hyperkalemia risk with supplements
Potassium-sparing diuretics (spironolactone, amiloride) — serious hyperkalemia risk
Digoxin — potassium levels directly affect digoxin toxicity; maintain careful balance