What is the recommended diet for a Chronic Kidney Disease (CKD) stage 5 patient on regular Hemodialysis (HD)?

Dietary Recommendations for CKD Stage 5 Patients on Regular Hemodialysis

For CKD Stage 5 patients on maintenance hemodialysis, prescribe a diet with 1.0-1.2 g/kg/day protein, 25-35 kcal/kg/day energy, sodium restriction to <2.3 g/day, phosphorus limitation to 800-1,000 mg/day (adjusted for protein needs), and individualized potassium restriction based on serum levels rather than blanket restrictions. 1, 2

Protein Requirements

Hemodialysis patients require significantly higher protein intake than pre-dialysis patients due to dialytic losses and increased catabolism. 1

• Target 1.0-1.2 g/kg body weight per day to maintain stable nutritional status and prevent protein-energy wasting 1
• For diabetic hemodialysis patients, the same 1.0-1.2 g/kg/day target applies, though higher levels may be needed if experiencing hyper- or hypoglycemia to maintain glycemic control 1
• Select protein sources limited in saturated fat and cholesterol, emphasizing lean meats, poultry, fish, and legumes 2
• There is insufficient evidence to recommend plant versus animal protein specifically, so both can be incorporated 1

The rationale for increased protein in dialysis: Unlike pre-dialysis CKD patients who benefit from protein restriction (0.55-0.60 g/kg/day), hemodialysis removes amino acids and increases protein catabolism, necessitating higher intake to prevent malnutrition. 1, 3

Energy Intake

• Prescribe 25-35 kcal/kg body weight per day based on age, sex, physical activity level, body composition, and presence of inflammation 1
• Energy needs may reach 35 kcal/kg/day in some hemodialysis patients 3
• Adjust based on weight status goals—higher end for underweight patients, lower end for overweight patients 1

Sodium Restriction

Sodium restriction is critical for blood pressure control, reducing interdialytic weight gain, and minimizing ultrafiltration requirements. 2

• Limit sodium to <2.3 g/day (approximately 5-6 g salt/day) 2, 1
• More stringent restriction to 1.0-1.5 g sodium/day (2.5-3.8 g salt) may be necessary for hypertensive dialysis patients 2
• A 5 g sodium chloride diet should result in approximately 1.5 kg average interdialytic weight gain in a 70 kg anuric patient on thrice-weekly hemodialysis 2
• Common pitfall: Focusing only on fluid restriction without addressing sodium intake fails because increased sodium stimulates thirst, perpetuating fluid overload 4

Phosphorus Management

Phosphorus control is essential to prevent bone disease and vascular calcification, but must be balanced against adequate protein intake. 1, 2

• Maintain serum phosphorus between 3.5-5.5 mg/dL in hemodialysis patients 1
• Restrict dietary phosphorus to 800-1,000 mg/day when serum phosphorus exceeds 5.5 mg/dL 1
• Estimate phosphorus needs by multiplying recommended protein intake by 10-12 mg phosphorus per gram of protein 2
• For patients >80 kg, it is nearly impossible to achieve adequate protein while limiting phosphorus to 1,000 mg, so adjust accordingly 2

Phosphate binder strategy: 1, 2

• Use calcium-based binders (calcium carbonate or calcium acetate) as initial therapy if serum calcium is not elevated 1
• Total elemental calcium from binders should not exceed 1,500 mg/day, and total calcium intake (including dietary) should not exceed 2,000 mg/day 1
• Do not use calcium-based binders if corrected serum calcium >10.2 mg/dL or PTH <150 pg/mL on two consecutive measurements 1
• Consider non-calcium binders (sevelamer, lanthanum) for patients with severe vascular calcification or persistent hyperphosphatemia despite calcium-based binders 1

Potassium Considerations

Potassium restrictions should be individualized based on serum levels rather than applying blanket restrictions to all hemodialysis patients. 2, 4

• Adjust potassium intake to maintain serum levels within normal range 2, 4
• Renal potassium excretion is typically maintained until GFR decreases below 10-15 mL/min/1.73 m², so some residual function may allow more liberal intake 4
• Traditional recommendations suggest limiting potassium to approximately 2,000-2,500 mg/day (50-65 mmol) for hyperkalemic patients 1
• Important nuance: Not all hemodialysis patients require strict potassium restriction; some may develop hypokalemia and require potassium supplementation or high-potassium foods 1

Practical tip for omega-3 foods: Foods high in omega-3 fatty acids (flaxseed, walnuts, soy) are also high in potassium, so use their oils (walnut, flaxseed, canola oil) instead to obtain cardiovascular benefits without excessive potassium 2

Fluid Restriction

• Restrict fluids to 1.5-2 L/day for oliguric/anuric patients to prevent fluid overload 2, 4
• Add 500-800 mL to residual urine output for patients with remaining kidney function 3
• Patients with residual kidney function may tolerate less restrictive limits 2

Foods to Emphasize

A balanced approach focusing on whole foods provides better outcomes than overly restrictive diets. 2, 5

• Consume omega-3 fatty acids at least twice weekly from cold-water fish (salmon, mackerel, herring, albacore tuna) or 1-4 g EPA/DHA from supplements 1, 2
• Low-fat or nonfat dairy products within phosphorus limits 2
• Fresh fruits and vegetables selected based on individual potassium tolerance 2
• Unsaturated fats from vegetables and oils (canola, walnut, flaxseed oils) 2
• Whole grains, though phosphorus binders may be needed due to phosphorus content 1

Cardiovascular Risk Reduction

Hemodialysis patients have extremely high cardiovascular mortality, making dietary modification for CVD risk essential. 2

• Limit saturated fats to <10% of total calories 2
• Restrict cholesterol to <300 mg/day 2
• Avoid trans-fatty acids completely 2
• Limit alcohol to 2 drinks/day for men, 1 drink/day for women 2

Micronutrient Considerations

• Supplement with water-soluble vitamins due to dialytic losses 3
• Maintain vitamin D (25(OH)D3) levels >30 ng/mL through supplementation if deficient 1, 6
• Monitor for deficiencies in calcium, iron, zinc, selenium, folate, and vitamin A, which are commonly inadequate in hemodialysis diets 7

Monitoring and Support

Regular dietitian involvement is essential for achieving dietary goals and preventing malnutrition. 1, 2

• Nutritional assessments should occur at least every 6 months 2
• Monitor appetite, dietary intake, body weight changes, biochemical data, anthropometric measurements, and nutrition-focused physical findings 1
• Use composite nutritional scores rather than albumin alone for assessment 2
• Frequent patient contact with a registered dietitian accomplishes dietary goals and improves clinical outcomes 1

Supplementation for Inadequate Intake

If dietary counseling alone fails to meet nutritional requirements: 1

• Consider a minimum 3-month trial of oral nutritional supplements for patients at risk of or with protein-energy wasting 1
• If oral intake remains inadequate, consider enteral tube feeding 1
• For severe protein-energy wasting unresponsive to oral/enteral nutrition, consider intradialytic parenteral nutrition (IDPN) 1

Critical Pitfalls to Avoid

• Do not apply overly restrictive potassium limits universally—some patients develop hypokalemia and need liberalization 1, 5
• Do not restrict protein to pre-dialysis levels—this causes malnutrition in dialysis patients 1, 3
• Do not ignore sodium while focusing only on fluid restriction—sodium drives thirst and worsens fluid overload 4
• Do not exceed 1,500 mg/day elemental calcium from phosphate binders—this increases vascular calcification risk 1
• Do not use calcium-based binders in hypercalcemic patients or those with PTH <150 pg/mL—this worsens low-turnover bone disease 1