During physical activity, muscle cells break down and form a waste product called creatinine. When the kidneys function normally, they remove creatinine from the bloodstream and eliminate it in the urine. When kidney function declines, creatinine builds up in the blood stream and causes problems that include fatigue, itchy skin and nausea. Special dietary restrictions help reduce creatinine levels.
Features
This type of diet restricts the intake of protein, phosphorus, potassium and sodium. In patients with advanced kidney disease, a diet designed to lower creatinine levels also restricts fluid consumption. Eating less protein reduces the workload of the kidneys, while eating less sodium, phosphorus and potassium prevents these substances from building up in the bloodstream. Reducing fluid intake prevents fluid from building up in the bloodstream, which reduces blood pressure and prevents swelling.
Effects
With a reduced workload, the kidneys do not have to work as hard to maintain normal fluid and electrolyte balances. Eating less protein reduces the amount of creatinine the body produces. Both of these things make it easier for the kidneys to filter creatinine out of the blood and reduce creatinine levels. Following this type of diet may also slow the progression of kidney disease.
Meal Planning
Patients on this type of diet must know which foods to eat and which foods to limit. High-potassium foods to avoid include tomatoes, oranges, potatoes, chocolate and nuts. People with kidney disease should avoid the sodium content of foods such as fast food, frozen meals, canned vegetables, pickled or cured meats, canned soups, cheese, salted pretzels and salted potato chips. Foods that contain high levels of phosphorus include corn, chocolate, dairy products, fish and eggs. Red meat, poultry, fish and nuts have high levels of protein.
Expert Insight
Although patients with kidney disease should limit their protein intake, they do not have to eliminate protein consumption. Peggy Harum, a registered dietitian for the American Association of Kidney Patients, explains that patients following this diet should eat 0.6 g of protein for every kg of body weight each day. This means a 160 lb. person would need to eat 43.6 g of protein each day. The Food and Nutrition Board recommends 46 g of protein per day for healthy females and 56 g of protein per day for healthy males.
Considerations
Because kidney disease increases the risk for diabetes, high blood pressure and heart disease, patients on this diet may find it necessary to control their carbohydrate intake or follow a low-fat, low-cholesterol diet. If you have questions about your diet, consult a dietitian or nutritionist for guidance. An experienced professional can develop an eating plan that will help you manage your kidney disease and any other medical conditions you develop.
References
- National Kidney and Urologic Diseases Information Clearinghouse: The Kidneys and How They Work
- MedlinePlus: Diet -- Chronic Kidney Disease
- DaVita: Potassium, Phosphorus and the Dialysis Diet
- American Association of Kidney Patients: What to Eat if You Have Chronic Kidney Disease
- Food and Nutrition Board: Dietary Reference Intakes
