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Potassium — Frequently Asked Questions

This content is for informational purposes only and does not constitute medical advice. Consult your healthcare provider before starting any supplement. Full disclaimer

Frequently Asked Questions

Why are potassium supplements limited to 99mg?

The FDA limits OTC potassium supplement capsules and tablets to 99mg per dose due to the risk of hyperkalemia (dangerously high blood potassium), which can cause fatal heart arrhythmias. This rule primarily protects people with kidney disease or those on potassium-retaining medications. Potassium-rich foods are not restricted because the body absorbs dietary potassium more gradually.

What foods are highest in potassium?

Top potassium sources include: baked potato with skin (926mg), sweet potato (542mg), white beans (1 cup = 1,189mg), banana (422mg), spinach (1 cup cooked = 839mg), avocado (727mg), and salmon (534mg per 6 oz). A diet rich in these foods can provide 3,000-4,700mg daily without supplements.

Who is at risk for potassium deficiency?

Groups at highest risk include: people taking thiazide or loop diuretics, those with chronic diarrhea or vomiting, heavy alcohol users, people with eating disorders, and individuals on very low-calorie diets. The standard American diet provides about 2,500mg daily — below the 3,400mg adequate intake for men.

References

  1. (). Effect of increased potassium intake on cardiovascular risk factors and disease: systematic review and meta-analyses. BMJ. DOI
  2. (). Potassium intake, stroke, and cardiovascular disease: a meta-analysis of prospective studies. Journal of the American College of Cardiology. DOI
  3. (). Potassium-magnesium citrate is an effective prophylaxis against recurrent calcium oxalate nephrolithiasis. Journal of Urology. DOI