Vitamin K
Vitamin K is a high-risk supplement with an RDA of 120 mcg and a tolerable upper intake level (UL) of 1000 mcg per day according to NIH/NASEM standards. All 3 regional standards agree on these limits. It has 3 known interactions with other supplements including vitamin d, vitamin d3, vitamin e. Regular monitoring is strongly recommended when adjusting your intake.
Quick take
Vitamin K sits in the Fat-Soluble Vitamins category. This page consolidates 3 regional standards, and the numbers are broadly aligned, so the bigger question is whether your total dose stays in range.
It also has 3 known interactions, so the question is not just the label dose but whether the rest of your stack adds extra risk.
Taking multiple supplements? Check Vitamin K for overlap
If Vitamin K appears on two product labels, enter each daily amount and check the combined label total.
Check Vitamin K across my supplementsFree. No account required.
Overdose Risk Warning
Vitamin K affects blood clotting; high doses can interact with warfarin and similar drugs.
Regional Reference Values
| Region | Organization | RDA | Upper Limit (UL) | Unit |
|---|---|---|---|---|
| 🇺🇸 United States | FDA | 120 | 1000 | mcg |
| 🇪🇺 Europe | EFSA | 120 | 1000 | mcg |
| 🇦🇺 Australia | TGA | 120 | 1000 | mcg |
RDA = Recommended Daily Allowance (adequate intake for most adults). UL = Tolerable Upper Intake Level; some authorities have not established one.
Known Interactions
Vitamin D increases calcium absorption; Vitamin K helps direct calcium to bones.
Consider taking both together for bone health.
Vitamin D3 increases calcium absorption; Vitamin K helps direct calcium to bones.
Consider taking both together for bone health.
High doses of Vitamin E may interfere with Vitamin K function.
Keep Vitamin E below 400 IU if taking blood thinners.
How to use this page
First match your product label against the dose table above, then check whether the known interaction list includes anything in your current stack.
If you are taking multiple supplements, the safest approach is usually to audit the whole stack instead of judging a single bottle in isolation.
Frequently Asked Questions
How much Vitamin K is too much?
FDA lists a formal upper limit (UL) of 1000mcg per day for Vitamin K. Other regions may use a different value or have no established UL.
What is the recommended daily dose of Vitamin K?
The RDA for Vitamin K is 120mcg per day for most adults. This amount is sufficient to meet the needs of 97-98% of healthy individuals.
Does Vitamin K interact with other supplements?
Yes, Vitamin K has 3 known interactions with other supplements. Vitamin D increases calcium absorption; Vitamin K helps direct calcium to bones.
Are you taking Vitamin K?
Check if your supplement stack keeps Vitamin K within safe limits.
Audit My SupplementsDisclaimer: NutriAudit is a decision-support tool designed to help you review your supplement stack for potential duplicate, conflicting, or excessive ingredients. It is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider before making changes to your supplement routine, especially if you are pregnant, nursing, taking medications, or have a medical condition.
Uses cited public reference data where the current dataset has a verified entry.