Potassium
The most under-consumed essential mineral — critical for blood pressure, heart rhythm, and muscle function
Also known as: Potassium Citrate • Potassium Chloride • Potassium Gluconate
Overview
Potassium is the most abundant intracellular cation and is essential for virtually every cell in the body. It maintains cell membrane potential, regulates fluid balance, supports nerve transmission, and enables muscle contraction (including the heart). Despite its critical importance, potassium is the most under-consumed nutrient in the American diet — 97% of Americans don't meet the Adequate Intake of 4,700mg/day. Low potassium intake is strongly associated with hypertension, stroke, kidney stones, and osteoporosis. The relationship between sodium and potassium is crucial: it's not just about reducing sodium, but about increasing the potassium-to-sodium ratio. Supplementation is limited by regulation — the FDA restricts potassium supplements to 99mg per dose due to the risk of hyperkalemia (dangerously high potassium) in susceptible individuals.
Key Benefits
Blood Pressure Reduction
Increasing potassium intake is one of the most effective dietary strategies for lowering blood pressure. Meta-analyses show that increasing potassium by 1,500-2,000mg/day reduces systolic BP by 3-5 mmHg. The DASH diet's blood pressure benefits are largely attributed to its high potassium content.
Stroke Prevention
Higher potassium intake is associated with a 24% lower risk of stroke. This benefit appears independent of blood pressure effects, suggesting potassium has direct protective effects on blood vessels and the brain.
Kidney Stone Prevention
Potassium citrate is a first-line treatment for calcium kidney stones. It alkalinizes urine, increases citrate excretion (which inhibits stone formation), and reduces calcium excretion. Studies show 40-50% reduction in stone recurrence.
Bone Health
Potassium-rich diets are associated with higher bone mineral density and reduced fracture risk. Potassium (especially as citrate) reduces urinary calcium loss by buffering metabolic acid, preserving calcium for bone maintenance.
Muscle Function & Cramp Prevention
Potassium is essential for muscle contraction and relaxation. Low potassium (hypokalemia) causes muscle weakness, cramps, and in severe cases, paralysis. Adequate potassium intake helps prevent exercise-related muscle cramps.
Dosage & How to Take
The Adequate Intake is 4,700mg/day for adults, but most people get only 2,500-3,000mg from diet. Supplements are limited to 99mg per dose by the FDA. The best strategy is to increase potassium-rich foods and use supplements as a modest addition.
| Purpose | Dose | Notes |
|---|---|---|
| General health (AI) | 4,700 mg/day from all sources | Primarily from food; supplements provide only a small fraction |
| Blood pressure support | Increase by 1,500-2,000 mg/day from food | Focus on potassium-rich foods like bananas, potatoes, beans |
| Kidney stone prevention | Potassium citrate 30-60 mEq/day (prescription) | Under medical supervision; prescription doses are much higher than OTC |
| Supplement dose | 99 mg per dose (FDA limit) | OTC supplements provide only 2% of daily needs |
Best Time to Take
Divide potassium intake throughout the day with meals. Large single doses can cause GI upset and potentially dangerous spikes in blood potassium.
With or Without Food
Always take with food to reduce GI irritation and slow absorption for safety.
Forms & Bioavailability
| Form | Absorption | Best For | Notes |
|---|---|---|---|
| Potassium Citrate | High | Kidney stones, alkalinizing | Best absorbed form. Alkalinizes urine. Preferred for kidney stone prevention. |
| Potassium Chloride | High | General supplementation | Most common form. Can cause GI irritation. Used in salt substitutes. |
| Potassium Gluconate | Good | Gentle on stomach | Lower elemental potassium per mg. Gentler on GI tract. |
| Potassium Bicarbonate | High | Alkalinizing, bone health | Buffers acid. May support bone health. |
Side Effects & Safety
Common
- GI upset (nausea, diarrhea, stomach pain)
- Metallic taste
Rare
- Hyperkalemia (dangerously high potassium — primarily in kidney disease or with certain medications)
- Heart rhythm disturbances (from hyperkalemia)
Contraindications
- Kidney disease (impaired potassium excretion)
- ACE inhibitors or ARBs (these medications raise potassium)
- Potassium-sparing diuretics (spironolactone, amiloride)
- Addison's disease
Interactions
These medications reduce potassium excretion; combined with supplements can cause dangerous hyperkalemia
Spironolactone, amiloride, triamterene all raise potassium; supplements can cause hyperkalemia
May reduce potassium excretion, especially in combination with ACE inhibitors
Potassium and sodium have opposing effects on blood pressure; increasing potassium-to-sodium ratio is beneficial
Scientific Research
Potassium and Blood Pressure Meta-Analysis
Increasing potassium intake by 1,500mg/day reduced systolic BP by 3.49 mmHg in adults
Potassium and Stroke Risk
Higher potassium intake was associated with 24% lower stroke risk in a meta-analysis of prospective studies
Potassium Citrate and Kidney Stones
Potassium citrate reduced kidney stone recurrence by 40-50% in randomized trials
Food Sources
Frequently Asked Questions
Medical Disclaimer
This content is for educational and informational purposes only and is not intended as medical advice. Always consult with a qualified healthcare professional before starting any supplement regimen, especially if you have pre-existing health conditions or are taking medications. The statements on this page have not been evaluated by the Food and Drug Administration.