
48. Potatoes and sweet potatoes are potassium-rich vegetables.
Just one medium-sized baked potato (156 g) contains 610 mg of potassium, whereas one average-sized baked sweet potato (114 g) contains 541 mg of potassium. Fortunately, some high-potassium foods, including potatoes and sweet potatoes, can be soaked or leached to reduce their potassium contents. Cutting potatoes into small, thin pieces and boiling them for at least 10 minutes can reduce the potassium content by about 50%. Potatoes that are soaked in water for at least 4 hours before cooking are proven to have an even lower potassium content than those not soaked before cooking. This method is known as “potassium leaching,” or the “double cook method.

However, not all is bad news for potato and sweet potato lovers. According to a study published in the Journal of Epidemiology in June 2005, eating sweet potatoes can lower kidney cancer risk. They showed that Japanese people who would consume sweet potatoes regularly were less likely to die of cancer. It is important to ask your doctor if you have any problems, like a history of calcium-oxalate kidney stones, before taking them out of your diet or adding just a bit to it. They may prescribe a diet low on phosphorus, sodium, and potassium.