Understanding Your Vitamin D2 and K1 Supplement Dosage
What You Have
Your supplement contains 800 IU of Vitamin D2 per 4 drops 1. This is clearly stated on the FDA drug label, which specifies that each mL contains 20 mcg (800 IU) of Vitamin D2 as ergocalciferol, along with 120 mcg of Vitamin K1 1.
Is This Dose Appropriate?
For most adults, 800 IU daily is a reasonable maintenance dose but may be insufficient for treating deficiency or achieving optimal levels 2.
Standard Recommendations by Age and Condition:
- Infants (0-12 months): 400 IU daily is the standard recommendation to prevent deficiency 2, 3
- Adults (19-70 years): 600 IU daily meets basic needs for 97.5% of the population, though 800-1000 IU is often recommended for optimal health 2
- Adults over 70 years: 800 IU daily is the minimum recommended dose 2
- Patients on enteral nutrition: Should receive at least 1000 IU per day 2
Important Limitation of Your Supplement:
Vitamin D2 (ergocalciferol) is significantly less effective than Vitamin D3 (cholecalciferol) 4. Research demonstrates that D3 is more potent at raising and maintaining serum 25-hydroxyvitamin D levels, has better binding to vitamin D binding protein, and has a longer shelf life 4. For supplementation purposes, D3 should be strongly preferred over D2 4.
When 800 IU Is NOT Enough:
If you have documented vitamin D deficiency (levels <20 ng/mL), you need significantly higher doses 5:
- Loading phase: 50,000 IU weekly for 8-12 weeks 5
- Maintenance after loading: 2,000 IU daily or 50,000 IU monthly 5
For patients with malabsorption conditions (inflammatory bowel disease, post-bariatric surgery, celiac disease), even higher doses of 4,000-5,000 IU daily may be required 2, 5.
Practical Guidance:
- If using this supplement for general health maintenance and you're a healthy adult, 4 drops daily (800 IU) is acceptable but consider switching to a Vitamin D3 product for better efficacy 4
- If treating documented deficiency, this supplement is inadequate—you need prescription-strength Vitamin D (typically 50,000 IU weekly) 5
- For infants, you would give 2 drops daily (400 IU), which meets the standard recommendation 2, 3
Safety Considerations:
Daily doses up to 4,000 IU are considered completely safe for adults, with some evidence supporting up to 10,000 IU daily for several months without adverse effects 2. Your 800 IU dose is well below any toxicity threshold 2.