With chronic kidney disease (CKD), the ability to excrete wastes and fluid is diminished and can eventually be lost completely. This requires many CKD and kidney transplant patients to modify certain nutrients in their diets. In 2020, the National Kidney Foundation (NKF) and the Academy of Nutrition and Dietetics (AND) compiled the most recent research studies and updated the Clinical Practice Guidelines for Nutrition in CKD (referred to as the Kidney Disease Outcomes Quality Initiative (KDOQI)). In 2021, Frontiers in Medicine reviewed the KDOQI guidelines and created a more accessible summary for CKD patients. Learn more about it here.*  

What is the best approach for a kidney diet in earlier stages of CKD? 

Since a kidney diet often has many restrictions, it can be complicated and difficult to manage. The KDOQI guidelines encourage reducing restrictions when possible. 

For patients in the early- to mid-stages of CKD, with kidney function or a glomerular filtration rate (GFR) above 60, a heart-healthy diet is generally recommended, which includes:

• High amounts of fruits, vegetables, legumes, fish, poultry, and whole grains, 
• Limited amounts of concentrated sweets and sodium (less than 2300 mg daily), and
• Avoidance of red and processed meats. 

Following the Mediterranean diet or the DASH (Dietary Approach to Stop Hypertension), diet may help delay CKD progression.

What is recommended for advanced CKD and transplant patients? 

For CKD stages 3-5 and kidney transplant patients without other significant health conditions, KDOQI guidelines recommend the following:

• Protein consumption should be restricted to approximately 0.6 grams per kilogram of body weight for patients with CKD stage 3-5, and 0.8 grams per kilogram for kidney transplant patients. Plant-based protein sources are preferable over animal-based ones to support kidney function and improve proteinuria (protein in the urine). 
• Limit sodium/salt intake to less than 2300 milligrams a day. Following a low-sodium diet may prevent toxic effects on blood vessels, improve blood pressure control, help with fluid control in the body, and decrease proteinuria. 
• Adjustments to phosphorus and/or potassium in the diet are only necessary to improve blood levels to a normal range. 
• When needed, weight loss through diet, lifestyle modifications, or surgery may improve blood pressure control, kidney function, and proteinuria in patients with kidney disease. 
• For CKD stages 3-5, probiotic supplementation may provide positive stomach and intestinal benefits that support kidney health. 

During CKD stages 3-5, or following a kidney transplant, there is often a need for further modifications; however, it is important that nutrition is still individualized. Speak with your doctor or renal dietitian to get more support on customizing your kidney diet. 

*Molina, P., Gavela, E., Vizcaíno, B. F., Huarte, E., et al. (2021). Optimizing Diet to Slow CKD Progression. Frontiers in Medicine, 8. https://doi.org/10.3389/fmed.2021.654250