The kidneys function to maintain acid-base balance and remove excess fluid and waste in the body. The kidneys may not function properly as a result of ischemic or nephrotoxic injury, sepsis, diabetes or hypertension. Low kidney function may be an acute or chronic condition, varying the medical pathway of treatment. A therapeutic diet may be prescribed to keep nutrients in the blood normalized, reduce fluid retention and prevent bone loss.
Low Potassium
Too much potassium in the blood may lead to heart problems such as an irregular heartbeat or heart attack. Many foods high in potassium are found in the fruit and vegetable groups. High potassium foods include avocados, greens, zucchini, bananas, potatoes, apricots, spinach, oranges and tomatoes. Foods lower in potassium such as apples, carrots, cauliflower, blueberries, corn, grapes, green beans, peaches, lettuce, pineapple and mushrooms should be selected. A potassium restriction of 3,000 to 4,000mg per day is recommended when serum potassium levels are greater than 5mg/dL.
Low Phosphorus
Phosphorus is needed for healthy bones, but in people who have limited kidney function, the body cannot remove excess phosphorus in the blood. Too much phosphorus in the body causes calcium loss and leads to brittle bones. When serum phosphorus levels are above 4.6mg/dL, limit dietary intake of phosphorus to 800 to 1,000mg per day. Foods high in phosphorus are cheese, dried beans, milk, nut butters, organ meats, soy milk, tofu and yogurt.
Low Sodium
High blood pressure, increased thirst and fluid retention are consequences from consuming too much sodium. Extra fluids may build up around the heart and lungs and cause difficulty breathing. Foods high in salt include soy sauce, pickles, cheese, processed meats, salty snack foods, frozen meals, canned soups and convenience side dishes. Choose foods that are less processed, limit dining out and do not use seasonings with salt. Suggested intake of sodium varies from 1,000mg to 4,000mg per day, depending on the level of kidney function.
References
- USDA National Nutrient Database for Standard Reference, Release 20: Potassium
- USDA National Nutrient Database for Standard Reference, Release 20: Phosphorus
- USDA National Nutrient Database for Standard Reference, Release 20: Sodium
- "A Clinical Guide to Nutrition Care in Kidney Disease"; American Dietetic Association; 2004
