Vitamin K1 (Phylloquinone)
Last updated: August 9, 2026
Benefits
Essential for normal blood clotting and works alongside vitamin K2 in bone metabolism.
How much you need
Recommended daily amounts by life stage, per NIH and NASEM Dietary Reference Intakes. Where the evidence hasn't been enough to set a full RDA (Recommended Dietary Allowance), NASEM sets an AI (Adequate Intake) instead — both are shown together below.
| Life stage | RDA / AI |
|---|---|
| Children 1–3 | 30 mcg |
| Children 4–8 | 55 mcg |
| Boys 9–13 | 60 mcg |
| Girls 9–13 | 60 mcg |
| Males 14–18 | 75 mcg |
| Females 14–18 | 75 mcg |
| Men 19–50 | 120 mcg |
| Women 19–50 | 90 mcg |
| Men 51–70 | 120 mcg |
| Women 51–70 | 90 mcg |
| Men 71+ | 120 mcg |
| Women 71+ | 90 mcg |
| Pregnancy 14–18 | 75 mcg |
| Pregnancy 19–50 | 90 mcg |
| Lactation 14–18 | 75 mcg |
| Lactation 19–50 | 90 mcg |
Upper limit
No tolerable upper limit has been established for Vitamin K1 (Phylloquinone). That doesn't mean unlimited amounts are risk-free — it means the evidence NASEM has reviewed so far hasn't been enough to set a numeric ceiling.
Best food sources
| Serving | ||
|---|---|---|
| Kale and collard greens | — | — |
| Spinach | — | — |
| Broccoli and Brussels sprouts | — | — |
| Parsley | — | — |
| Vegetable oils | — | — |
Absorption & caution
Absorption: Fat-soluble — absorbs best alongside a meal that contains some fat, and unlike water-soluble vitamins, extra amounts are stored in the body rather than excreted.
Caution: If you take warfarin, vitamin K is the nutrient that matters most: it works against the medication, so a swing in your intake moves your INR. The goal is steadiness — keep your intake about the same day to day rather than cutting it out, and talk to your clinician before starting or stopping a vitamin K supplement or making a big change in leafy greens.
Body systems & goals
Body systems it supports
- Bones — Bone is living tissue that's always being renewed, drawing on these nutrients to stay dense and strong. Supporting them now helps your body maintain a sturdy frame for years to come. (emerging evidence)
Frequently asked questions
How much Vitamin K1 (Phylloquinone) do adult women need per day?
Adult women (19–50) need 90 mcg of Vitamin K1 (Phylloquinone) per day, per NIH/NASEM Dietary Reference Intakes.
How much Vitamin K1 (Phylloquinone) do adult men need per day?
Adult men (19–50) need 120 mcg of Vitamin K1 (Phylloquinone) per day, per NIH/NASEM Dietary Reference Intakes.
Does pregnancy change how much Vitamin K1 (Phylloquinone) you need?
No — the recommended amount stays at 90 mcg per day during pregnancy (ages 19–50).
Is there an upper limit for Vitamin K1 (Phylloquinone)?
No tolerable upper limit has been established for Vitamin K1 (Phylloquinone), based on current evidence reviewed by NASEM.
What foods are highest in Vitamin K1 (Phylloquinone)?
Good sources include Kale and collard greens, Spinach, Broccoli and Brussels sprouts, Parsley, and Vegetable oils.
How Tavita handles this
Tavita logs Vitamin K1 (Phylloquinone) from both the food you eat and the supplements you take, adding both into one running daily total. There's no established upper limit for Vitamin K1 (Phylloquinone), so Tavita tracks it against the recommended amount without implying a ceiling that doesn't exist.
Sources
Figures on this page come from the NIH Office of Dietary Supplements fact sheets and the National Academies of Sciences, Engineering, and Medicine (NASEM) Dietary Reference Intake tables — the same dataset that powers the Tavita app. They were independently re-verified by blind re-derivation on August 9, 2026. See the methodology page for how this library is built and kept current.
Tavita is not a medical provider. This page is educational information, not medical advice — talk to your clinician before changing your supplement or medication routine.