ADEK Vitamin Supplementation: Recommended Daily Dosages
The recommended daily dosages for ADEK vitamins vary significantly based on clinical context, with bariatric surgery patients requiring substantially higher doses than general populations: Vitamin A 6,000-10,000 IU, Vitamin D 3,000 IU (titrated to serum levels), Vitamin E 100-400 IU, and Vitamin K 300 μg-10 mg daily. 1
Context-Specific Dosing Recommendations
For Bariatric Surgery Patients (Post-RYGB, Sleeve Gastrectomy, BPD/DS)
Vitamin A:
- Routine supplementation: 6,000 IU daily included in multivitamin for standard bariatric procedures 1
- After BPD/DS: 10,000 IU daily due to severe malabsorption 1
- For pregnant women or those planning conception, use β-carotene form (provitamin A) rather than retinol to avoid teratogenicity 1
- Keep vitamin A intake below 10,000 IU/day in pregnancy 1
Vitamin D:
- Standard dose: 3,000 IU daily (as ergocalciferol or cholecalciferol) 1
- Titrate to achieve serum 25(OH)D ≥30 ng/mL 1
- After correction of deficiency, maintenance typically requires 2,000-4,000 IU daily, though BPD/DS patients may need up to 7,000 IU daily 2
Vitamin E:
- Routine dose: 100-400 IU daily of α-tocopherol 1
- After BPD/DS: 400 IU daily 1
- Use water-miscible formulations for enhanced absorption in malabsorptive procedures 2
Vitamin K:
- After BPD/DS: 300 μg daily 1, 2
- Standard bariatric procedures: Include in multivitamin at recommended daily intake levels 1
For Cystic Fibrosis Patients with Pancreatic Insufficiency
Vitamin A:
- Dosing is dependent on serum values and supplement form 1
- Retinol (preformed): Start low, adapt rapidly to target normal serum reference range 1
- Beta-carotene (provitamin A): 1 mg/kg/day (maximum 50 mg/day) for 12 weeks, followed by maintenance dose (maximum 10 mg/day) 1
Vitamin D:
- Infants: 400 IU/day (advance to upper limit of 1,000 IU/day) 1
- All others: 800 IU/day (advance to upper limit of 2,000 IU/day for children 1-10 years, and 4,000 IU/day for older children and adults) 1
- Target serum 25(OH)D minimum 20 ng/mL (50 nmol/L) 1
Vitamin E:
Vitamin K:
Critical Implementation Considerations
Formulation Selection
- Water-miscible (solubilized) forms of vitamins A, D, E, and K significantly improve absorption in patients with fat malabsorption 2, 3
- Standard fat-soluble vitamin preparations may fail in severe malabsorption states 2
- The risk of hypervitaminosis A is higher with water-miscible and water-soluble forms than oil-based supplements 1
Monitoring Requirements
- Monitor serum levels annually and 3-6 months after dosage changes for all fat-soluble vitamins 1
- Do not assess vitamin A during acute infection when serum retinol falls in response to inflammation 1
- For vitamin D, preferably measure at the end of dark months when levels are lowest 1
Essential Co-Supplementation
- Separate calcium supplements by 2 hours from iron or multivitamins containing iron 1
- Provide 2 mg copper daily when supplementing zinc (15 mg zinc for standard bariatric, 30 mg for BPD/DS) to prevent zinc-induced copper deficiency 4
- Maintain zinc-to-copper ratio of 8:1 to 15:1 4
Common Pitfalls to Avoid
Toxicity Risk:
- Factor in dietary intake when determining supplement dosing to avoid vitamin A toxicity 1
- Vitamin D intoxication can occur with compounding errors, presenting with hypercalcemia and digestive symptoms 5
Absorption Interference:
- Take fat-soluble vitamins 2-4 weeks after bariatric surgery, not immediately 1
- GERD and PPI use impair fat-soluble vitamin absorption; monitor these patients more closely 6
Treatment Failure: