People with end-stage renal disease have kidneys that no longer function properly to remove waste from their bodies. Dialysis treatment removes waste products and excess fluid from the blood, in place of the kidneys. People on dialysis treatment typically follow a special diet to help control blood levels of certain elements, such as potassium, phosphorus, sodium and protein. Some vegetables contain potassium and should be limited by those on dialysis.
Role of Potassium
Potassium plays a vital role in the function of nerve and muscle cells throughout the body, including regulating heart rhythm. When potassium levels are too high, it's known as hyperkalemia. When they are too low, it's called hypokalemia. Both conditions can be fatal.
Potassium and Dialysis
Typically, the kidneys filter out and excrete excess potassium from the blood. For people with end-stage renal disease, the dialysis machine filters out excess potassium. The amount of potassium you consume in your diet directly affects the amount of potassium in your blood. People on dialysis are asked to follow a strict diet and consume no more than 2 to 4 grams of potassium per day. The amount of potassium you should consume each day depends on the type of dialysis you receive as well as your lab values. A normal serum potassium level is 3.5 to 5.0 mEq/L.
Vegetables to Limit and Avoid
Certain vegetables contain significant amounts of potassium. These vegetables are not be recommended for consumption by patients receiving dialysis. All varieties of potatoes, including sweet potatoes, should be avoided, as they are high in potassium. Other vegetables that are high in potassium include tomatoes, winter squash, pumpkin, avocado, beets, asparagus and spinach.
Low Potassium Vegetables
Not all vegetables are significant sources of dietary potassium. Summer squash, zucchini, broccoli, cauliflower, green and wax beans, celery, peppers, onions, and cucumbers do not contain large amounts of potassium, although they do contain some. These vegetables should be consumed more often than those high in potassium in order to keep potassium levels within a safe range.
Other Sources of Potassium
Potassium is not only found in vegetables, but in fruits, legumes, salt substitutes, and dairy products as well. All of these sources of potassium should be taken into consideration by people who undergo dialysis. Your doctor can help you develop a healthy diet for your individual needs.