What is the best diet to follow for individuals with impaired renal function (kidney failure)?

Best Diet for Kidney Failure

For individuals with kidney failure, the optimal diet should include plant-based foods over animal-based foods, protein intake of 0.8 g/kg body weight/day, sodium restriction to <2g/day, and limited ultra-processed foods, with individualized adjustments based on CKD stage and comorbidities. 1, 2

Protein Management

General Recommendations

• Maintain protein intake at 0.8 g/kg body weight/day for adults with CKD G3-G5 2
• Avoid high protein intake (>1.3 g/kg body weight/day) in adults at risk of CKD progression 1
• Ensure adequate energy intake (30-35 kcal/kg/day) to prevent protein-energy wasting and maintain nitrogen balance 1

Special Considerations

• For patients at high risk of kidney failure: Consider a very low-protein diet (0.3-0.4 g/kg/day) supplemented with essential amino acids or ketoacid analogs, but only under close supervision 2
• For children: Do not restrict protein intake due to growth impairment risk; target the upper end of normal range 2
• For older adults with frailty/sarcopenia: Consider higher protein and calorie targets 2, 1
• For patients on dialysis: Higher protein intake (1.2-1.4 g/kg/day for hemodialysis; 1.5 g/kg/day for peritoneal dialysis) 3

Sodium and Fluid Management

• Limit sodium intake to <2g/day (<5g sodium chloride/day) 2, 1
• Exception: Sodium restriction is not appropriate for patients with sodium-wasting nephropathy 2
• For patients on hemodialysis: Water intake should be residual diuresis plus 500-800ml 3
• For children with blood pressure >90th percentile: Follow age-based Recommended Daily Intake for sodium 2

Plant-Based vs. Animal-Based Foods

• Emphasize plant-based foods over animal-based foods 2, 1
• Plant-dominant low-protein diet (PLADO) with at least 50% plant-based protein sources offers benefits including reduced uremic toxin production 1
• Plant proteins from seeds and legumes contain phosphorus in phytate form, which is less bioavailable and may be advantageous 4
• Special vegan diets with appropriate cereal-legume mixtures can provide complementary proteins while reducing acid load 5

Phosphorus Management

• Select foods with lower phosphorus-to-protein ratios 4
• Be aware that inorganic phosphorus in food additives and processed foods is more readily absorbed than organic phosphorus in natural foods 4
• Limit phosphorus intake, particularly in advanced CKD stages 6

Potassium Considerations

• Restrict potassium in advanced CKD (typically <1 meq/kg/day for hemodialysis patients) 3
• Peritoneal dialysis patients may tolerate higher potassium intakes (2000-3000 mg/day) 3

Practical Implementation

• Consult with renal dietitians for individualized dietary education 2, 1
• Monitor nutritional status regularly through serum albumin levels, body weight, and dietary interviews 1
• Conduct biannual nutrition screening for all CKD patients 1

Common Pitfalls to Avoid

• Overly restrictive diets can lead to malnutrition and increased mortality risk 1
• Very low protein diets (<0.6 g/kg/day) without proper supplementation have been associated with increased mortality 1
• Processed foods may contain hidden phosphorus additives not accurately reflected in nutrition labels 4
• Focusing solely on protein restriction without ensuring adequate caloric intake can lead to protein-energy wasting 1, 6

The diet for kidney failure requires careful balance between restricting potentially harmful nutrients while ensuring adequate nutrition to prevent malnutrition. Working with a renal dietitian is essential to tailor these recommendations to individual needs based on CKD stage, comorbidities, and nutritional status.