Diet and Dialysis
Dialysis, or hemodialysis, is the most common treatment method for advanced and permanent kidney failure.
Normal kidneys help to clean the blood by removing harmful wastes and excess fluid. In addition, they also make hormones, which keep the bones strong and the blood healthy. When the kidneys fail, it can lead to buildup of harmful wastes in the body, elevation of blood pressure, buildup of excess fluid, and a decline in red blood cells. When this occurs, treatment to replace the work of the failed kidneys is necessary.
In hemodialysis, the patient’s blood is allowed to flow through a special filter that removes wastes and extra fluids. The clean blood is then returned to the body.
Following a strict diet can help improve your dialysis and your health. A dietitian can help you plan meals. Following your dietitian’s advice is important to get the most from your hemodialysis treatments. Here are a few general guidelines.
- Fluids. By limiting how much fluid you drink each day, you can prevent extra fluid from building up in your body. Extra fluid can cause your blood pressure to rise, which makes your heart work harder, and increase the stress of dialysis treatments. Many foods—such as fruits, soup, and ice cream—contain plenty of water. Your dietitian can help you determine how much to drink each day. He or she can also provide you with tips on how to control your thirst.
- Phosphorus. Consuming too much of the mineral phosphorus can result in weakening of bones and can make your skin itchy. Having too much phosphorus in your blood can cause calcium to be pulled out from your bones. Foods high in phosphorus—such as milk and cheese, peas, dried beans, nuts, colas, and peanut butter—should be avoided. You probably will need to take phosphate binder to control the phosphorus in your blood between dialysis sessions. Your dietitian can provide you with more specific information regarding phosphorus.
- Potassium. The mineral potassium effects how steadily your heart beats. It is found in many foods, especially milk and fruits and vegetables, such as avocados, oranges, bananas, tomatoes, potatoes, and dried fruits. Consuming too much foods high in potassium can be very dangerous to your heart. Your dietitian can give your more specific information about potassium and the potassium content of foods.
- Protein. Before you were on dialysis, your doctor may have told you to follow a low-protein diet. Being on dialysis changes this. Most people on dialysis are encouraged to eat as much high-quality protein as they can. Protein helps you keep muscle and repair tissue. The better nourished you are, the healthier you will be. You will also have greater resistance to infection and recover from surgery more quickly.
Your body breaks protein down into a waste product called urea. If urea builds up in your blood, it’s a sign you have become very sick. Eating mostly high-quality proteins is important because they produce less waste than others. High-quality proteins come from meat, fish, poultry, and eggs (especially egg whites).
- Calories. Calories provide your body with energy. Some people on dialysis need to gain weight. You may need to find ways to add calories to your diet. Vegetable oils—like olive, canola, and safflower oils—are good sources of calories and do not contribute to problems controlling your cholesterol. Hard candy, sugar, honey, jam, and jelly also provide calories and energy. If you have diabetes, however, be very careful about eating sweets. A dietitian’s guidance is especially important for people with diabetes.
- Supplements (vitamins and minerals). Because you have to avoid so many foods, vitamins and minerals may be missing from your diet. In addition, dialysis also removes vitamins from your body. Your health care provider may prescribe a vitamin and mineral supplement, which is specifically designed for people with kidney failure. You should avoid taking vitamin supplements that you can buy off the store shelf. They may contain vitamins or minerals that may be harmful to you.
Talk with your doctor or dietitian about foods that you can take when you are receiving dialysis treatments.
National Kidney and Urologic Diseases Information Clearinghouse (December 2006). Treatment Methods for Kidney Failure: Hemodialysis (NIH Publication No. 07—4666). National Diabetes and Digestive and Kidney Diseases (NIDDK), National Institutes of Health (NIH), Bethesda, MD. Web URL: http://kidney.niddk.nih.gov/kudiseases/pubs/hemodialysis/index.htm. Accessed: November 15, 2008
National Kidney and Urologic Diseases Information Clearinghouse (August 2008). Eat Right to Feel Right on Hemodialysis (NIH Publication No. 08—4274). National Diabetes and Digestive and Kidney Diseases (NIDDK), National Institutes of Health (NIH), Bethesda, MD. Web URL: http://kidney.niddk.nih.gov/kudiseases/pubs/eatright/. Accessed: November 15, 2008