Potassium is well absorbed from the small intestine, with about 90 percent absorption, but is one of the most soluble minerals, so it is easily lost in cooking and processing foods. When we perspire a great deal, we should replace our fluids with orange juice or vegetable juice containing potassium rather than just taking salt tablets. The kidneys are the chief regulators of our body potassium, keeping the blood levels steady even with wide variation in intake. The adrenal hormone aldosterone stimulates elimination of potassium by the kidneys. This mineral is also lost with vomiting and diarrhea.
Potassium is found in a wide range of foods.
Many fruits and vegetables are high in potassium and low in sodium and, as discussed, help prevent hypertension. Most of the potassium is lost when processing or canning foods, while less is lost from frozen fruits or vegetables. Leafy green vegetables such as spinach, parsley, and lettuce, as well as broccoli, peas, lima beans, tomatoes, and potatoes, especially the skins, all have significant levels of potassium. Fruits that contain this mineral include oranges and other citrus fruits, bananas, apples, avocados, raisins, and apricots, particularly dried. Whole grains, wheat germ, seeds, and nuts are high-potassium foods.