📋 KDOQI Guidelines on Nutrition in Chronic Kidney Disease

Domain 1

🔍 Nutritional Status Assessment

Why is it important?

Regular nutritional assessment helps detect malnutrition early - a common problem in kidney patients that increases mortality risk.

Indicators to assess:

• Weight and BMI: Monitor weight changes over time
• Dietary intake: Assess daily protein, energy, and nutrient intake
• Blood tests: Albumin, prealbumin (transthyretin), CRP
• Body composition: Assess muscle and fat mass
• Muscle strength: Test hand grip strength, mobility

Domain 2

🍽️ Medical Nutrition Therapy (MNT)

What is MNT?

MNT is intensive nutrition intervention provided by a registered dietitian, including personalized counseling, meal planning, and close monitoring.

Benefits of MNT:

• Slows kidney disease progression
• Reduces cardiovascular complications risk
• Improves blood glucose control in diabetic patients
• Reduces uremic toxin accumulation
• Delays the need for dialysis

Components of MNT:

1. Initial assessment: Dietary history, preferences, culture, economic conditions
2. Personalized planning: Based on CKD stage, lab tests, health status
3. Patient education: Detailed guidance on foods to eat and avoid
4. Monitoring and adjustment: Assess adherence, effectiveness, adjust plan

Domain 3

🥩 Protein and Energy Intake

A. Protein Recommendations

B. Energy (Calorie) Recommendations

• Pre-dialysis CKD: 25-35 kcal/kg/day
• Elderly (>60 years): 30-35 kcal/kg/day
• Dialysis patients: 30-35 kcal/kg/day
• Adjust based on activity level, age, and weight goals

C. Ketoanalogues Diet (VLPD)

Very Low Protein Diet (VLPD, 0.3-0.4g/kg/day) combined with ketoanalogues of amino acids may:

• Slow CKD progression
• Reduce uremic toxins
• Improve mineral metabolism
• Delay the need for dialysis by 1-2 years

This diet should only be implemented under close supervision of a physician and dietitian.

Domain 4

💊 Nutritional Supplements

A. When are supplements needed?

Nutritional supplements are recommended when:

• Unable to meet nutritional needs through regular diet
• Signs of malnutrition (weight loss, low albumin, muscle loss)
• Loss of appetite due to illness or surgery
• Preparing for surgery or kidney transplant

B. Types of supplements:

1. Oral Energy and Protein Supplements

• Specialized renal formulas (low phosphorus, potassium)
• Help increase energy and protein without increasing kidney waste
• Typical use: 1-2 servings/day between main meals

2. Intradialytic Parenteral Nutrition (IDPN)

• Intravenous nutrition during dialysis
• For severely malnourished dialysis patients
• Requires careful risk-benefit assessment

Domain 5

🔬 Micronutrients

A. B Vitamins

Why are they important? CKD patients are prone to B vitamin deficiency due to reduced food intake, dietary restrictions, and losses through dialysis.

• Vitamin B6 (Pyridoxine): Important for protein metabolism
• Vitamin B12 (Cobalamin): Needed for red blood cell formation
• Folate (B9): Reduces homocysteine, protects cardiovascular health
• Niacin (B3): May be used to control phosphorus

Recommendation: Dialysis patients should take a B-complex vitamin supplement daily.

B. Vitamin D

CKD patients are often deficient in vitamin D due to:

• Reduced kidney conversion of vitamin D to active form (calcitriol)
• Restriction of dairy and vitamin D-rich foods (due to high phosphorus)
• Limited sun exposure

Recommendations:

• Measure 25(OH)D levels at least once per year
• Supplement with vitamin D2 or D3 when deficient
• May need active form (calcitriol) in late-stage CKD

C. Iron

Iron deficiency anemia is very common in CKD patients.

Causes:

• Reduced erythropoietin (EPO) production by kidneys
• Blood loss during dialysis
• Reduced iron absorption
• Chronic inflammation

Recommendations:

• Monitor ferritin, TSAT (transferrin saturation) regularly
• Supplement with oral or IV iron when needed
• Target: Ferritin >100 ng/mL, TSAT >20% in pre-dialysis patients

D. Antioxidants

Vitamin C, vitamin E, and selenium have antioxidant roles but require caution:

• Vitamin C: Should not supplement >90 mg/day (risk of increased oxalate)
• Vitamin E: May be beneficial but needs more research
• Selenium: Supplement when deficiency is proven

Domain 6

⚖️ Electrolytes and Minerals

A. Sodium

Target: < 2.3 grams sodium/day or 100 mmol/day (equivalent to < 5.8 grams table salt)

Note: CKD patients with diabetes should restrict to < 2g sodium/day per KDIGO 2020

Benefits of sodium restriction:

• Reduces blood pressure by 5-10 mmHg
• Reduces edema
• Reduces cardiovascular burden
• Increases effectiveness of blood pressure medications
• Slows CKD progression

How to implement:

• Limit salt when cooking
• Avoid processed foods, canned goods, sausages, pickles
• Read nutrition labels, choose "low sodium" products
• Use aromatic herbs instead: ginger, garlic, basil, lemon
• Do not use salt substitutes (KCl) as they are high in potassium

B. Potassium

Target: Maintain blood potassium in normal range (3.5-5.0 mEq/L)

Risks of high blood potassium (>5.5 mEq/L):

• Dangerous cardiac arrhythmias
• Muscle weakness
• Numbness and tingling
• Possible sudden death

Recommendations:

• Potassium intake: 2-3 g/day when blood potassium is high
• Limit high-potassium foods: bananas, oranges, potatoes, tomatoes, watermelon, spinach
• Potassium-reduction techniques: soak vegetables in water for 2 hours, boil and discard water
• Regular blood potassium testing

C. Phosphorus

Target: 800-1000 mg/day, maintain blood phosphorus < 4.5 mg/dL

Why restrict phosphorus?

• High phosphorus causes renal osteodystrophy (kidney bone disease)
• Calcification of blood vessels and heart valves
• Increased cardiovascular mortality risk
• Uncomfortable skin itching

Phosphorus sources to avoid:

• Dairy products: Cheese, yogurt, ice cream (high in easily absorbed phosphorus ~80%)
• Processed foods: Cola sodas, processed meats, frozen foods
• Nuts: Almonds, cashews, peanuts
• Carbonated drinks: Pepsi, Coca-Cola contain phosphoric acid

Tips to reduce phosphorus:

• Choose almond milk or rice milk instead of cow's milk
• Prefer fresh meat and fish over processed
• Read labels: avoid additives with "phosph" (phosphate, phosphoric acid)
• Take phosphate binders with meals if prescribed

D. Calcium

Target: 800-1000 mg/day from food and supplements

Notes:

• Total calcium (food + phosphate binders) should not exceed 2000 mg/day
• High calcium + high phosphorus = risk of vascular calcification
• Calcium-phosphorus balance is very important

E. Fluid

For pre-dialysis patients:

• Usually no restriction needed if urinating well
• Drink adequate 1.5-2 liters/day unless experiencing edema or advised by physician to restrict

For dialysis patients:

• Restriction: 750-1000 mL/day + remaining urine output
• Calculation: Daily fluid = 24-hour urine output + 500-750 mL
• Goal: Weight gain between dialysis sessions < 2-2.5 kg (< 5% dry weight)
• Tips: Use small cups, suck on ice chips, rinse mouth without swallowing

🆕 Differences from Previous Guidelines

1. Expanded scope: Applies to all CKD stages (1-5) and kidney transplant recipients, not just dialysis patients as before.
2. Stronger evidence base: Analysis of over 15,000 studies using rigorous GRADE methodology.
3. Personalization: Emphasizes individualizing diet plans rather than rigidly applying one formula for all.
4. Role of MNT: Enhanced role of dietitians, recommending CKD 3-5 patients see a dietitian early.
5. Focus on quality of life: Not only prolonging life but also improving patients' quality of life.
6. Specific practical guidance: Provides detailed guidance on how to monitor, assess, and adjust diet.

🎯 Key Messages for Patients

📊 Evidence of Effectiveness

Studies and meta-analyses on nutritional interventions in CKD show:

• Reduced rate of kidney function decline with low protein diet adherence: Each 0.2 g/kg/day protein reduction decreases GFR decline rate by approximately 1.15 ml/min/1.73m²/year and halves the risk of kidney failure or death (MDRD study analysis)
• Lower blood pressure and cardiovascular protection with sodium restriction <2.3g/day: Reduces blood pressure by 5-10 mmHg, increases effectiveness of blood pressure medications, reduces cardiovascular burden
• Delayed dialysis with VLPD diet in CKD 4-5 patients: Garneata 2016 study showed very low protein diet (0.3 g/kg/day) combined with ketoanalogues reduced dialysis risk by 84% and mortality by 78%, delaying dialysis by approximately 11 months compared to no intervention
• Improved quality of life with Medical Nutrition Therapy (MNT) adherence: Reduced uremic symptoms, fewer complications, improved blood glucose control in diabetic patients
• Phosphorus and calcium control helps prevent renal bone disease, vascular calcification, and reduces cardiovascular mortality risk
• Significant reduction in healthcare costs due to fewer complications, delayed dialysis, and reduced hospitalization frequency

📝 Daily Checklist for CKD Patients

Daily self-check:

✓ Protein:

• Have I eaten adequate but not excessive protein as recommended?
• Is at least 50% from high-value sources (eggs, fish, meat)?

✓ Salt:

• Avoid adding salt to food
• Don't eat processed foods, canned goods, pickles
• Use natural seasonings instead

✓ Potassium:

• Avoid bananas, oranges, potatoes if blood potassium is high
• Soak vegetables before cooking

✓ Phosphorus:

• Limit dairy, cheese, carbonated drinks
• Read labels to avoid phosphate additives
• Take phosphate binders with meals (if prescribed)

✓ Fluid:

• Drink adequate if urinating well
• Restrict if on dialysis (follow physician's guidance)

✓ Medications and vitamins:

• Take vitamin B, vitamin D as prescribed
• Supplement iron if anemic

🍎 Sample One-Day Menu for CKD Stage 3-4 Patient

For a male patient, 70kg, protein 0.8g/kg (56g/day), energy 2100 kcal

Breakfast (7:00):

• 1 bowl rice porridge or sticky rice (100g rice)
• 1 boiled/fried egg
• Boiled vegetables: cauliflower, broccoli (pre-soaked)
• 1 glass unsweetened almond milk

Morning Snack (10:00):

• 1 apple or 1 cup strawberries
• 3-4 unsalted crackers

Lunch (12:00):

• 1 bowl white rice (100g rice)
• 80g grilled or steamed salmon/mackerel (no salt)
• Pumpkin soup with a little garlic (no onion)
• Stir-fried vegetables: cabbage, carrots (olive oil, garlic)
• 1 bowl cucumber

Afternoon Snack (15:00):

• 1 glass strawberry smoothie + rice milk
• 1 slice sandwich bread (low salt) + jam

Dinner (18:00):

• 1 bowl white rice (100g rice)
• 70g boiled or grilled chicken breast (skin removed)
• Vegetable soup: squash, carrots, green beans (pre-soaked)
• Boiled or stir-fried vegetables: bok choy, malabar spinach

Before Bed (21:00):

• 1 serving renal formula (if supplementation needed)