Fruits that are low in potassium include apples, blackberries, blueberries, cranberries, grapes, lemons, peaches, pears, pineapples, plums and strawberries. Many vegetables such as cabbage, carrots, cauliflower, corn, cucumbers, eggplant, green beans, lettuce, mushrooms, radishes and water chestnuts are low in potassium. Other foods, such as rice, noodles, pasta, breads, coffee and tea, are also low in potassium. The appropriate portion size for these foods is one-half cup.
When more than the portion size of any low-potassium food is eaten, the amount of potassium is increased, making it a food higher in potassium. A low-potassium diet may be indicated when kidney disease prevents the proper elimination of potassium from the body, causing potassium levels to rise. An irregular heartbeat or heart attack can result from potassium levels that are too high. When following a low-potassium diet, it is best to eat a wide variety of foods in moderation. Some high-potassium vegetables can be leached by soaking in water to lower the amount of potassium in them.
Some fruits that should be avoided on a low-potassium diet include apricots, bananas, cantaloupe, nectarines, oranges, prunes and tomatoes. Vegetables that are high in potassium include artichokes, avocado, beets, chard, leafy greens, okra, parsnips, sweet potatoes and spinach.