When mice eat a lot of salt, adding a moderate amount of potassium lowers their blood pressure, showing that potassium's main benefit might be fighting high blood pressure caused by salt.

In mice eating normal salt, too much potassium (over 1.75% of their diet) makes their blood pressure go up during active hours, especially at high potassium levels like 5%, because of increased activity of certain kidney channels.

When mice eat a lot of salt, adding a moderate amount of potassium lowers their blood pressure by about 3.6 mmHg compared to eating the same high salt without extra potassium.

Using salt with more potassium might lower blood pressure the most in people who usually eat very little potassium but a lot of salt—like some adults living in rural China.

When people who don’t eat much potassium switch to salt with extra potassium, their blood pressure drops mostly because they’re getting more potassium—not because they’re eating less salt, since they’re still eating plenty of salt.

Eating more potassium-rich foods like bananas and spinach can help lower your blood pressure and make it less likely you'll have a stroke or heart problem—especially if you're eating a lot of salty foods.