Decades of research have suggested that our sodium habit is killing us via hypertension and heart disease. But other research suggests it's not salt's fault after all. So, which is it?

Salt, it turns out, has not been acting alone. A new study, published in the Archives of Internal Medicine, implicates potassium, too. Not enough potassium. [Quanhe Yang, et al., "Sodium and Potassium Intake and Mortality Among US Adults"]

The study surveyed more than 12,000 Americans, and found that both men and women consumed way more sodium and way less potassium than is recommended. And after 15 years, people with the better balance of sodium and potassium were more likely to still be alive.

In whole plants, sodium is scarce and potassium is plentiful. But when foods are processed, that ratio is usually flipped. The two elements have opposite effects on blood vessels: sodium restricts blood flow and potassium helps it. The researchers thus suggest cutting back on salt and taking in more potassium. So forget the chips—a banana is a safer snack for your health. Just watch where you toss the peel.

—Katherine Harmon

[The above text is a transcript of this podcast.]