Polycystic Kidney Disease Diet
A person with advanced kidney disease due to polycystic kidney disease may need to avoid some foods and limit the amount of others. Waste products that failing kidneys cannot handle include protein, sodium, potassium, and phosphorus.
General Dietary Restrictions
When the kidneys are not working normally, waste products (blood urea nitrogen), the result of what we eat, build up in the bloodstream. Kidney dialysis (kidney machine) removes part of these byproducts temporarily until, once again, they accumulate. It is important for both the patient who is dependent upon dialysis, or suffering from compromised kidney function, to follow a carefully outlined diet. Typical dietary restrictions will be placed on total calories, fluids, protein, sodium, phosphorus, and potassium. Supplemental calcium is also required by many patients.
Calories are a measurement of the energy value of food. They are an essential part of any diet. The number of calories you eat affects your ability to gain and lose weight. An inadequate number of calories will burn protein derived not only from the protein that you eat, but also from the body's own muscle stores. A healthy diet must give your body both the required amount of protein for tissue growth and repair, as well as enough calories for your energy needs. Excess calories and protein will put an unnecessary strain on a diseased kidney.
When the kidneys are no longer functioning efficiently, fluids accumulate in the body. Fluid overload can contribute to shortness of breath, hypertension, and swelling of the hands, legs, and feet. This condition can lead to congestive heart failure and excess build up of fluid in the lungs. Fluids are defined as liquids, including foods that melt to a liquid at room temperature. Since fluid overload is dangerous, it is important to limit your intake. Keeping track of your weight every day can allow you to early detect any trend of fluid retention.
The balance of fluid in the human body is partly regulated by the mineral sodium. When sodium is combined with chloride, it forms table salt. Excessive amounts of salt in the diet result in the retention of too much water. This may cause a sudden increase in weight, swelling of the tissues and joints, high blood pressure, shortness of breath, and congestive heart failure. Most foods contain sodium either naturally or as additives. High sodium foods include processed and smoked meats, foods with salt toppings such as chips or nuts, sauces, and prepared and canned foods.
Many kidney disease patients must limit their sodium intake to 2 grams per day or less.
The mineral potassium plays a key role in the normal functioning of the muscles and nerves as well as in regulating the pumping action of the heart. Muscle weakness and cardiac arrhythmias may be the result of high levels of potassium in the blood. Since the heart is a muscle, a buildup of potassium may lead to sudden death (cardiac arrest). Potassium is found in many foods and in salt substitutes. Your potassium level should be monitored closely. A dangerously high blood potassium level in a patient with end-stage kidney disease is a criterion for emergent kidney dialysis.
The body uses protein for the growth and repair of tissues. Normally, protein byproducts are excreted from the body in the urine. When kidney function is impaired, the end product of protein metabolism, urea, accumulates in the bloodstream. The best kind of protein to eat is the kind that is used most efficiently by the body. Doing this leaves the least amount of protein waste behind. These proteins are referred to as complete or high quality proteins that contain most of the essential amino acids. High quality proteins include eggs, meat, fish, fowl, and some dairy products. Low quality proteins are found in foods such as vegetables, fruits, breads, cereals, and starches.
Calcium and Phosphorus
The balance of calcium and phosphorus in the body is crucial to the maintenance of healthy bones, muscles, and nerves. Renal disease contributes to the imbalance of these important minerals. Too much phosphorus may cause the bones to become brittle and break easily. This results from the body's removal of calcium in the bones to balance the excess phosphorus. Foods high in phosphorus are usually also high in potassium (another mineral that must be restricted). Phosphorus rich foods are dairy products, meats, shellfish, bran, whole grain products, beans, nuts, and chocolate. Calcium is found in most dairy products, but will need to be supplemented (OS-CAL) in most cases.
Vitamins and Minerals
Vitamin and mineral supplements such as (OS-CAL) are frequently needed since dietary restrictions may prevent a renal patient from receiving all the needed nutrients necessary for a healthy and balanced diet. Kidney dialysis can also remove vitamins from the bloodstream. Vitamin supplements should only be prescribed by a physician in patients with kidney disease.
Continue to Polycystic Kidney Disease Warning Signs
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