The kidneys are vital organs that remove toxins from the blood. They also assist in regulating blood pressure and producing hormones that prevent anemia. Patients go on dialysis when their kidneys can no longer perform all these functions. A dialysis machine performs some of the functions of the kidney, including filtering the blood.
Most dietary guidelines for dialysis patients are driven by the patient's laboratory results. Nutritionists and doctors use these results when making dietary restrictions.
Protein
Prior to starting dialysis, many patients limit the amount of protein they eat because their damaged kidneys can no longer filter protein waste and eating protein makes them nauseated, or they have been advised to restrict protein to control protein levels in their urine. According to DaVita.com, once a patient is on dialysis, these concerns no longer apply. Dialysis patients require a higher amount of protein because dialysis removes certain essential amino acids from the blood.
Phosphorus
High phosphorus levels are a problem for many patients with advanced kidney disease. Unfortunately, this problem does not go away when starting dialysis because dialysis is not particularly good at removing phosphorus from the blood. While some patients are able to reduce phosphorus levels by taking phosphorus binders prescribed by their physician, others find it necessary to eat fewer high phosphorus food such as potatoes and all-bran cereal. Decreasing phosphorus is often at odds with the need to increase protein because many high protein foods such as milk, milk products, dried beans and nuts are also high in phosphorus. Patients are better off getting their dietary protein through meat and chicken and occasionally fish.
Just like the days before dialysis, phosphorus levels are monitored through regular lab tests. Any dietary changes should be in response to these tests so that the patient does not restrict the diet unnecessarily.
Water
Patients on dialysis often have a limited ability to produce urine. While dialysis removes excess fluids that have built up between dialysis sessions, patients still have to restrict their fluid intake. Limiting salt may help minimize thirst between dialysis sessions. The National Institutes of Diabetes and Digestive and Kidney Diseases advises that patients ask their nutritionist how much fluid is safe for them to drink.
Potassium
Potassium remains a problem for many patients even after starting dialysis, according to the National Institutes of Diabetes and Digestive and Kidney Diseases. Since the kidneys no longer remove potassium from the blood, levels of potassium in the blood can get so high that they cause heart attacks. The best way to avoid this is by sticking to a low potassium diet.
Fortunately, many high potassium foods such as potatoes, sweet potatoes, rutabaga, squash and other vegetables can still be eaten if the potassium is first leached from the food. Patients can cut the food into small bites, soak it in water for several hours, rinse and then cook the food as they normally would. This procedure makes it easier to stay on a low potassium diet.
