The substitute is the same crystals with a quarter to two-thirds of the sodium replaced by potassium chloride. Two levers pull at once: less sodium goes in, more potassium goes in, and both drop blood pressure ¹. The catch: your kidneys clear extra potassium only when an adrenal hormone tells them to. Block that hormone with the wrong pill, or damage the kidneys, and potassium builds up in the blood instead. A day's use adds about a banana's worth, which a healthy person never notices.

One large, simple trial carries the case. Twenty-one thousand rural Chinese adults, all with high blood pressure or a prior stroke, got a 75/25 sodium-potassium shaker or their usual salt, assigned by village. Five years later: fewer strokes, fewer heart attacks, fewer deaths, systolic pressure about 3 mm Hg lower ¹. A nursing-home trial saw cardiovascular events nearly halve ², and a meta-analysis across thirty-two thousand people found the same mortality signal ³. Heart and kidney guidelines now name it as a tool ⁴.

First, find out which group you're in. The decision turns on your kidneys and your pills. Read the contraindications below; if none apply, the swap is nearly free and lifelong.

Nothing dramatic happens, and that is the point. The first two weeks taste like nothing changed. By week four a home cuff reads two to four points lower; by two months the full effect has landed, sometimes enough to defer a second pill ². At five years the switched version of you carries a one-in-seven smaller chance of a stroke and a one-in-eight smaller chance of death ¹. Stroke prevention is invisible until it isn't.

Thiazide and loop diuretics (hydrochlorothiazide, furosemide) lower potassium, so the swap is usually fine on those; the label or the pharmacist tells you which kind you take. In the US and UK only about a quarter of sodium comes from the home shaker, so expect less than the full trial effect if much of your food is restaurant or packaged.