Vitamin D3 + K2 Dosage: How Much to Take (IU & mcg) + Best Time
vitamin d3 k2 dosage
directing calcium where it’s needed. But the most common question is simple: what is the right vitamin D3 + K2 dosage?
In this guide, you’ll learn beginner-friendly dosage ranges, how to read labels (IU vs mcg), best timing, and safety tips.
Disclaimer: This content is educational and not medical advice. If you take prescription medications (especially blood thinners) or have a medical condition, consult a healthcare professional.
Quick Dosage Summary (for most adults)
If you want a simple starting point:
- Vitamin D3: 1,000–2,000 IU daily for general maintenance
- Vitamin K2 (MK-7): 90–120 mcg daily (common range in many combos)
If you’re using a high-potency product (like 5,000 IU D3), you may not need it daily unless advised by labs/clinician.
IU vs mcg: How to read Vitamin D3 labels
Vitamin D3 is often shown as IU, sometimes also as micrograms (mcg).
Conversion:
- 1 mcg = 40 IU
So: - 25 mcg = 1,000 IU
- 50 mcg = 2,000 IU
- 125 mcg = 5,000 IU
This matters because two products can look “different” but be the same dose.
Dosage Table (Beginner → High Potency)
| Goal | Vitamin D3 range | Vitamin K2 (MK-7) range | Notes |
|---|---|---|---|
| General maintenance | 1,000–2,000 IU/day | 90–120 mcg/day | Best for most beginners |
| Low sun exposure / winter | 2,000 IU/day | 90–120 mcg/day | Consider consistent daily use |
| Higher-potency protocol | 5,000 IU/day (or 4–6 days/week) | 100–200 mcg/day | Better guided by labs |
| Already taking a multivitamin with D | Add only if needed | keep K2 consistent | Avoid stacking too much D |
Best time to take Vitamin D3 + K2
Because both are fat-soluble, take them:
- With a meal that includes fat (lunch or dinner often works best)
- If D3 makes you feel more alert, take it morning/lunch, not before bed
Can you take it at night?
Yes, but some people report sleep disruption from vitamin D. If that happens, move it earlier.
Should you take D3 + K2 every day?
It depends on your dose.
If your product is 1,000–2,000 IU:
Daily use is common for maintenance.
If your product is 5,000 IU:
Some people take it less frequently (example: 4–6 days per week) depending on lifestyle and lab results.
Tip: More isn’t always better. Consistency + appropriate dose wins.
What K2 dose should you use: MK-7 vs MK-4?
Most iHerb combo products use K2 as MK-7, often around 90–120 mcg, because it’s convenient and common in daily formulas.
MK-4 exists too, but many daily combo supplements use MK-7.
Who should be careful (important)
1) People taking warfarin (Coumadin)
Vitamin K can affect warfarin therapy. Do not start K2 without medical guidance.
2) Kidney disease / history of kidney stones
High vitamin D can affect calcium handling—be cautious.
3) Hypercalcemia (high calcium) or parathyroid issues
Avoid self-supplementing with high-dose D3.
How long should you take D3 + K2 before changing dose?
- Give it 3–8 weeks before judging results
- If possible, check 25(OH)D blood levels (vitamin D status)
Common mistakes that cause side effects
- Taking high-dose D3 daily + adding a multivitamin that also contains D
- Taking D3 without food (worse absorption)
- Ignoring medication interactions (especially blood thinners)
- Using multiple supplements with overlapping ingredients
CTA
Want a quality D3 + K2 combo?
FAQ :
What is the best vitamin D3 + K2 dosage for beginners?
Most beginners start with 1,000–2,000 IU of D3 and 90–120 mcg of K2 (MK-7) daily, depending on diet and sun exposure.
Is 5,000 IU vitamin D3 too much?
For some people it can be more than needed, especially long-term. Many use it only when labs show low levels or under guidance.
Can I take magnesium with vitamin D3 + K2?
Many people combine magnesium because it supports vitamin D metabolism. Follow labels and avoid mega-dosing.
Should I take D3 + K2 with food?
Yes—fat-soluble vitamins absorb better with meals, and it can reduce stomach discomfort.
How long does it take to work?
Vitamin D status changes over weeks. Many people re-check levels after 6–8 weeks.