Replacing some ordinary salt with potassium salt can cut the risk of stroke. Researchers randomly assigned roughly 21,000 people living in 600 rural Chinese villages to use either ordinary salt (sodium chloride) or a salt that was 75 percent sodium chloride and 25 percent potassium chloride. All the participants had a history of stroke or were 60 or older and had poorly controlled blood pressure (140 or higher with drugs or 160 or higher without drugs).