What foods are suitable for patients undergoing dialysis?

Dietary Guidelines for Dialysis Patients

Dialysis patients should focus on consuming lean proteins (1.2-1.4 g/kg/day), fatty fish at least twice weekly for omega-3 fatty acids, and limiting sodium to less than 2.3 g/day while individualizing potassium and phosphorus restrictions based on laboratory values rather than applying blanket restrictions. 1

Core Macronutrient Requirements

Protein Intake

• Consume 1.2-1.4 g/kg body weight/day of protein to prevent muscle wasting and maintain nutritional status 2, 1
• At least 50% should be high biological value proteins from lean meats, poultry, fish, and eggs 2
• Selection of protein-rich foods should emphasize those limited in saturated fat and cholesterol 2

Energy Requirements

• Target 35 kcal/kg body weight/day for metabolically stable dialysis patients 2, 1
• For patients under 60 years: 35 kcal/kg/day 2
• For patients over 60 years: 30 kcal/kg/day 2

Specific Foods to Emphasize

Omega-3 Rich Foods

• Consume fatty fish (salmon, mackerel, herring, albacore tuna) at least twice weekly 2
• Cold-water fish provides EPA and DHA, which are more physiologically potent than plant-based omega-3s 2
• Use canola oil, walnut oil, and flaxseed oil as cooking oils rather than whole nuts/seeds, since whole forms are high in potassium 2

Protein Sources

• Lean meats and poultry 2, 1
• Fish and seafood 2, 1
• Eggs 2
• Legumes (within potassium limits) 2, 1
• Low-fat or nonfat dairy products (within phosphorus restrictions) 2, 1

Fats and Oils

• Limit saturated fats to less than 10% of total calories 2, 1
• Emphasize unsaturated fats from vegetable oils 2, 1
• Avoid trans-fatty acids completely 2
• Keep cholesterol intake below 300 mg/day 2, 1

Fruits and Vegetables

• Select fresh fruits and vegetables based on individual potassium tolerance rather than blanket restrictions 1, 3
• Whole grains can be incorporated within phosphorus limits 2

Critical Restrictions

Sodium Management

• Restrict sodium to less than 2.3 g/day (approximately 5-6 g salt/day) 2, 1
• This controls blood pressure, reduces interdialytic weight gain, and minimizes ultrafiltration requirements 1
• Focus on avoiding processed and restaurant foods, which contain 80% of dietary sodium 2
• For hypertensive patients, more stringent restriction to 1-1.5 g sodium (2.5-3.8 g salt) may be needed 1

Phosphorus Control

• Limit phosphorus while maintaining adequate protein intake, typically 10-12 mg phosphorus per gram of protein 1
• For patients over 80 kg, estimate phosphorus needs by multiplying recommended protein intake by 10-12 mg 1
• Use phosphate binders (calcium-based or non-calcium alternatives like sevelamer) when dietary restriction alone is insufficient 1
• Avoid processed foods with phosphorus additives, which are more readily absorbed than natural food phosphorus 3

Potassium Individualization

• Adjust potassium intake to maintain serum levels within normal range rather than applying universal restrictions 1, 4
• Renal potassium excretion is typically maintained until GFR decreases below 10-15 mL/min/1.73 m² 1
• Overly restrictive potassium diets may deprive patients of heart-healthy foods and lead to more atherogenic dietary patterns 4

Fluid Restriction

• Limit fluids to 1.5-2 L/day for oliguric or anuric patients 1
• Patients with residual kidney function may tolerate less restrictive limits 1
• Fluid restriction prevents interdialytic weight gain and reduces cardiovascular stress 1

Vitamin and Mineral Supplementation

Water-Soluble Vitamins

• Folic acid: 1 mg/day 2
• Pyridoxine (B6): 10-20 mg/day 2
• Vitamin C: 30-60 mg/day 2

Other Supplements

• Vitamin D should be given according to serum calcium, phosphorus, and parathyroid hormone levels 2
• Zinc: 15 mg/day in depleted patients 2
• Selenium: 50-70 µg/day in depleted patients 2

Alcohol Considerations

• If consuming alcohol, limit to 2 drinks/day for men and 1 drink/day for women 2, 1
• Alcohol has higher caloric density than protein and carbohydrate, providing "empty" calories 2
• Alcohol can be addictive and associated with hypertension, liver damage, and other adverse consequences 2

Implementation and Monitoring

Professional Support

• Receive expert dietary counseling from trained renal dietitians with individualized assessment 2, 1, 5
• Nutritional assessments should occur at least every 6 months 2, 1
• Dietary interviews every 6 months, body mass index and normalized protein nitrogen appearance (nPNA) monthly 2
• Serum albumin and transthyretin every 1-3 months according to nutritional status 2

Critical Pitfall to Avoid

Overly restrictive diets can lead to malnutrition, which is an independent predictor of mortality in dialysis patients 2, 4. The traditional approach of restricting fruits, vegetables, nuts, legumes, dairy, and whole grains may result in frustration, lack of autonomy, and worse nutritional outcomes 3. A more balanced, individualized approach focusing primarily on sodium and inorganic phosphorus restriction while liberalizing other nutrients based on laboratory values improves quality of life without compromising safety 4, 3.