In the search for rich dietary supplies of potassium, many people turn to bananas, which are sometimes pointed to as being the best natural source of the element. While the fruit certainly packs a potassium punch – roughly 400 milligrams per one half cup, according to the Centers for Disease Control and Prevention (CDC) – new research has suggested that potatoes may provide even more of the nutrient, relative to their cost.

A study presented at the American Dietetic Association’s Food and Nutrition Conference and Expo estimated that, for the amount of potassium they provide, white potatoes are at least twice as cheap as the next most cost-effective source of the mineral.

“Potatoes deserve credit for contributing to higher diet quality and increasing vegetable consumption,” lead researcher Adam Drewnowsk noted. He and his team added that potassium is particularly difficulty to consume inexpensively.

Of course, one viable alternative to the potato is a regular vitamin supplement, which can deliver a full day’s worth of potassium and many other important nutrients without necessarily draining your wallets.