Potassium for Cardiovascular Disease
Higher potassium intake is consistently linked to lower stroke risk and modestly lower cardiovascular events, but the strongest trial evidence comes from a potassium-enriched salt substitute eaten as food, not from potassium supplement pills. There is solid, caveated support for raising dietary potassium, while the supplement-capsule route for heart disease remains essentially untested.
Why this grade7-layer evidence engine
This earns a B (Preliminary Evidence, published with a warning) because the totality of data is genuinely supportive yet cannot be cleanly attributed to potassium pills. The pivotal evidence is the SSaSS randomized trial (PMID 34459569, ~21,000 adults), where a 75% salt / 25% potassium-chloride substitute cut stroke (RR 0.86), major cardiovascular events (RR 0.87) and all-cause death (RR 0.88) with no excess clinical hyperkalemia. A secondary analysis (PMID 38465623) also found fewer acute coronary syndromes (RR 0.80) and arrhythmias (RR 0.59).
Observational meta-analyses agree, but with an important nuance: higher potassium intake tracks with roughly 13-24% lower stroke risk (PMID 23558164 RR 0.76; PMID 21371638 RR 0.79; PMID 27792643 RR 0.87). Crucially, links to total cardiovascular disease and coronary heart disease are weaker and often reach significance only after sensitivity or exclusion analyses, so the benefit applies most firmly to stroke rather than to heart disease as a whole.
Regulators reinforce a solid-but-qualified verdict: the WHO strongly recommends increasing potassium from food to lower blood pressure and cardiovascular, stroke and coronary risk, the US FDA permits a health claim that potassium-rich, low-sodium diets may reduce high blood pressure and stroke, and Mayo Clinic frames dietary potassium plus modest salt restriction as protective. The grade is capped because the trial paired added potassium with cut sodium, and because people with chronic kidney disease or on ACE inhibitors, ARBs or potassium-sparing diuretics were excluded and face real hyperkalemia danger; high-dose potassium is prescription-regulated.
Scoring transparency
All scores computed by a 7-layer evidence engine — fully auditable▸View the full decision path (audit trail)
- compute_raw_score — 加權公式: L2×0.30 + L3×0.25 + L5×0.25 + L11×0.10 + L1×0.10 = 0.72
- tier_from_score — 依分數區間映射至 tier letter
- apply_hec_rules — 高品質 SR/MA 顯示 positive (1 篇 > 0 negative)
- tier_strict_requirement_check — | A→B 因 scope.conflation_risk=true 且 L11 獨評較低 (B7-2 tier cap)
- detect_disputes — 偵測到 0 個 hard + 0 個 soft dispute
- decide_status — 依 tier + dispute 結果決定 status