Potassium

Potassium keeps fluid balance, nerve signals and muscle contraction working, including the heartbeat. Food is the main and safest source. Searches for 'electrolytes' land here, but electrolyte products are a category rather than one ingredient and differ widely in how much potassium, sodium, magnesium or sugar they contain.

Potassium salts differ in taste, gastrointestinal tolerance and the accompanying anion. Chloride is used medically for low potassium; citrate is used where alkalinisation is desired.

Potassium is the main positively charged ion inside cells. The sodium-potassium pump maintains the gradient that allows nerve impulses and muscle contraction, and potassium intake influences sodium handling and vascular tone.

Higher dietary potassium is consistently associated with lower blood pressure and lower stroke risk in population studies, and trials of increased intake show modest blood-pressure reductions. Evidence specifically for supplements, rather than food or salt substitutes, is more limited. Treating documented low potassium is standard medical care.

Physiological and animal studies describe renal potassium handling, aldosterone regulation and cardiac electrophysiology under high and low potassium conditions.

Evidence gap: Non-human and mechanistic work. It explains the safety boundaries rather than adding proven supplement benefits.

Potassium is absorbed easily and removed by the kidneys. Medicines that reduce potassium excretion — including several blood-pressure drugs — plus reduced kidney function make high blood potassium possible, which can disturb heart rhythm.

High blood potassium can be life-threatening and may cause few symptoms before affecting heart rhythm. Anyone with chronic kidney disease, adrenal insufficiency, type 1 diabetes with poor control, or who takes ACE inhibitors, angiotensin receptor blockers, spironolactone or potassium-sparing diuretics should not take potassium supplements or salt substitutes without clinician supervision and blood monitoring. Solid oral potassium can also irritate or ulcerate the gut. No potassium product is universally safe: the risk depends on kidney function, medicines and dose.

Food, salt substitutes, tablets, capsules and electrolyte powders are all sources. Prescription potassium chloride is used for documented deficiency under monitoring.

Increasing potassium-rich foods within an overall dietary pattern, reducing sodium, and reviewing medicines are the usual first approaches for blood pressure. Supplemental potassium is primarily a treatment for documented deficiency rather than a general wellness product, and it does not replace blood-pressure treatment.

Educational example: an adult taking an ACE inhibitor and spironolactone starts a potassium-containing electrolyte powder plus a salt substitute and develops dangerously high potassium without warning symptoms. The decision factors are kidney function, medicines that retain potassium, and the total from all sources including foods and salt substitutes. Questions for a clinician or pharmacist: is potassium safe with my medicines and kidney results, and do I need blood monitoring? Hydration marketing rarely mentions that potassium content is a clinical variable.