Chronic Kidney Disease (CKD), also known as Chronic Renal Failure (CRF), currently affects 2 out of every 1,000 people in the United States with numbers projected to rise due to the incidence of diabetes. Following a renal diet can be a challenge since it is more restrictive and limiting, especially for those not currently on a dialysis treatment regimen. It is best to seek guidance from your physician and registered dietitian for particular macronutrient, micronutrient, calorie, and vitamin and mineral needs specific to your condition and individual factors, but the basic foundation of nutritional concerns to keep in mind are outlined here.
Chronic Kidney Disease Nutrition
Protein is essential to repairing and maintaining the body and all its functional components. However, it is essential to get the right amount in order to maintain the best kidney function (if not on dialysis) or to help repair and build (if on dialysis, which requires more). Again, the amount will be different and is best prescribed for your needs by your physician and registered dietitian. Reducing excess protein will decrease the production of nitrogenous waste and metabolic acids allowing your kidneys to work more efficiently prior to dialysis. In general, many protein foods are also rich in potassium and phosphorus, which can affect your bone and heart health. It is important to keep the portions small and the frequency consistent and limited.
Protein foods with a high biological value (HBV) are most effectively used by the body. These include lean meats, chicken and all other poultry, seafood, and eggs. Protein bars, supplements, and gels may also be used to increase intake and limit potassium and phosphorus consumption. Because dairy products, beans, and nuts, as well as nut butters, are higher in phosphorus, they need to be limited to small or half servings no more than once daily.
Aiming for 1500 mg-2000 mg (2g) Sodium (Na) is ideal. Most of the excess salt comes directly from the salt shaker or as a preservative in pre-packaged and processed foods. Eating fresh or frozen fruits and vegetables (stick with choices lower in potassium), low or no-sodium cheese, salad dressing, peanut butter and avoiding cured, preserved, packaged meals, soups, crackers, snacks, and condiments will be beneficial in reducing sodium intake.
Some herbs and spices that can replace salt are:
- Dry mustard
Label and ingredient reading will be also be helpful. On the nutrition facts label, 5% is considered low and 20% or more sodium is high. Some other words for salt/sodium on the ingredient label include: MSG, sodium nitrate, baking soda (sodium bicarbonate) and sodium chloride. Potassium chloride is also often used to replace sodium, but is not appropriate in CKD for the high potassium content. Consider a heart AND kidney friendly baking soda substitute such as Ener-G Sodium Free Baking Soda!
Fruits and vegetables of all kinds tend to have high levels of potassium. Particularly watching intake of items such as: bananas, beans, potatoes (leaching the potassium form the potatoes if appropriate-once or twice per week), tomatoes, fresh fruits, and melons; replacing these kind of items with broccoli, cauliflower, canned green beans, canned fruits, and canned corn will be beneficial in lowering potassium intake Other suggestions for lowering potassium are:
- Cooking with onions, peppers, mushrooms and garlic vs. tomatoes and chili sauces
- Drinking apple, cranberry, or grape juice vs. orange or prune juice
- Avoiding avocados and artichokes and using cucumber, cabbage, carrots, and snow peas for salads and stir-fry’s
Phosphorus is often found in protein-rich items. It is specifically higher in dairy items, whole grains, wheat, biscuits, corn bread, and beans. Some helpful suggestions in lowering phosphorus intake are:
- Vegan cheese/cheese substitutes
- Angel food cake, Rice Krispy treats
- Sorbet, sherbet, popsicles
- Non-dairy milks/creamer, Rice Dream beverage, or other un-enriched non-dairy beverages
- Substituting low-salt snacks such as pretzels, tortilla chips, and popcorn for nuts and seeds
- Using low-fat cream cheese, jams, and jellies vs. nut butters (or limiting to 1 Tbsp. peanut butter)
When appropriate, phosphate binders may be prescribed to be taken before meals to further reduce phosphorus levels. Calcium and parathyroid hormone levels will also be monitored in conjunction with phosphorus levels. When phosphorus levels are elevated, calcium is pulled from the bones in order to achieve homeostasis, leading to risk of decreased bone density and possible calcification of other organs.
Fluid is important to keep a close eye on in regards to hypertension, dilution of electrolytes, serum albumin, and filtering ability of your kidneys. It is suggested to not take in more than 32 oz. per day or output plus 500-1000 mL when on dialysis. Tips that may be helpful in limiting fluid intake include:
- Sucking on hard candy or chewing gum when one is thirsty
- Rinse mouth, practice proper oral care
- Having a jar filled with 32 oz. of water and rationing that amount for the day
- Avoid salty and processed foods, cured meats, and salty snacks
- Control blood sugar levels
- Ask about medications that may be affecting dry mouth
Vitamins/Minerals– Other concerns include vitamin and minerals, specifically:
- Vitamin C
- Vitamin B-6
- Vitamin B-12
- Vitamin E
- and Vitamin D
A renal diet may be overwhelming at first, but with proper education and tools, it is manageable and a registered dietitian can help tailor the diet to your specific needs. With a little direction and specific points, a pleasurable and enjoyable diet can be enjoyed on a daily basis.