Potatoes! They’re one of the world’s favorite vegetables. You can mash them, bake them, fry them, put them in salads, soups and they’re always delicious. The starchy tuber may be beloved, however, when it comes to people living with kidney issues, potatoes can present problems. Notably a high potassium content, a mineral level that typically ought to be closely monitored by anyone with kidney issues.

Although there are some workarounds including blanching and boiling, many people don’t find the resulting end product as tasty as potatoes which have been prepared using different cooking methods. A study sought to delve into this quandary, aiming to compile a definitive analysis of which cooking methods effectively reduce the potato’s potassium content while maintaining integrity and flavor.

So, how did science go about tackling this dilemma? Researchers studied potatoes in three distinct forms: fresh, canned and frozen french fried. These were further delineated by cut method: strips and diced. Potassium content was measured at both beginning and end of  study along with the percentage of humidity from each cooking method applied.

The final results indicated that soaking potatoes wasn’t terribly effective at removing potassium for fresh, raw potatoes. Neither was normal cooking. Leaching, however, which essentially means cooking the potato first and then soaking did remove about 70% of the potato’s potassium content, which translated to 130 mg’s worth of potassium. Frying afterwards caused a slight spike in potassium, but this spike didn’t exceed 150 mg. Similar results were also observed with the two other varieties: canned potatoes and frozen french fries.

The researchers were pleased with their findings, citing acceptably low potassium content when this ‘cook and soak’ method was employed, even after subsequent frying. So, although this doesn’t mean you should be eating french fries every day, it does allow for a very occasional indulgence here and there depending on what your current potassium levels are as well as what your nephrologist permits. The majority of the time, you should still be maintaining a good healthy kidney diet meaning low potassium all around and no frying!