Swapping table salt cut strokes in 21,000 villagers

Researchers at the George Institute for Global Health tested a simple substitute, three-quarters sodium chloride and one-quarter potassium chloride, as the only cooking and table salt in hundreds of villages across rural China, rather than asking individuals to cut back on salt on their own.

Nearly 21,000 people with a stroke history, or aged 60 and over with high blood pressure, were randomized by village to the substitute or to regular salt and followed for about five years. Those using the substitute had 14 percent fewer strokes, 13 percent fewer major cardiovascular events, and 12 percent fewer deaths from any cause.

Because the intervention changed the cooking salt itself rather than relying on individual willpower, it avoided the adherence problems that undermine many dietary advice trials. The substitute raises blood potassium slightly, so it is not recommended for people with advanced kidney disease, and public health agencies are now weighing whether to promote similar substitutes beyond this trial's rural Chinese setting.

One ingredient swap, fewer strokes across 600 villages.