English version in progress: interface and data are in English; some explanatory text is still in Chinese.
Vitamin K
维生素 K 让凝血蛋白"激活"；华法林正是通过对抗这一步起作用，所以摄入量要稳定。
Full ranking Dose tool Products (2,173)
Key facts
Daily Value (US FDA)120 mcg
Tolerable Upper Intake Level (UL)—
Median（Per day）65 mcgP5 8 – P95 20,000
Products2,173
Sources: https://ods.od.nih.gov/factsheets/VitaminK-HealthProfessional/ · FDA DV 120 mcg (https://www.fda.gov/food/nutrition-facts-label/daily-value-nutrition-and-supplement-facts-labels); pre-2016 DV [80] (https://www.federalregister.gov/documents/2016/05/27/2016-11867/food-labeling-revision-of-the-nutrition-and-supplement-facts-labels); no UL set; hard_high=100000 per serving (UL x10 or market maximum), hard_low=DV/1000
How it works：维生素 K 为什么和华法林有关？
- 维生素 K 有 K1（叶绿醌，主要来自绿叶蔬菜）和 K2（甲萘醌类）两类。
- 它是 γ-谷氨酰羧化酶的辅因子，负责"激活"一组依赖维生素 K 的蛋白。
- 被激活的凝血因子（II、VII、IX、X）参与正常凝血。
- 骨钙素等骨骼蛋白也需要这一步激活。
Schematic only; positions and scale are not anatomical.
Limits and cautions：未设定 UL。服用华法林者应保持维生素 K 摄入稳定，变化前先问医生。
Sources：NIH ODS: VitaminK Fact Sheet for Health Professionals
Daily dose across products（mcg/day）
DV 120
4.5 mcglog scale · n=2,17360,000 mcg
Label data from official national databases and brand websites, as declared; not lab-verified.
Common forms
| Form | Products | Median | P5–P95 | Elemental fraction |
|---|---|---|---|---|
| Vitamin K1 (phylloquinone) | 974 | 60 mcg | 10 – 500 | — |
| Vitamin K2 MK-7 | 429 | 70 mcg | 8 – 180 | — |
| Vitamin K2 MK-4 | 115 | 100 mcg | 50 – 5,000 | — |
Top ranked
| Rank | Brand | Product | Per day | Score |
|---|---|---|---|---|
| 1 | USANA | Vitamin K2 | 180 mcg | 90.0 |
| 2 | Thorne Research | Vitamin K2 | 45,000 mcg | 85.0 |
| 3 | Whole Foods Market | Vitamin K2 | 100 mcg | 81.3 |
| 3 | The Vitamin Shoppe | Vitamin K2 100 mcg | 100 mcg | 81.3 |
| 3 | Nature Made | Vitamin K2 100 mcg | 100 mcg | 81.3 |
For information only; not medical advice. Talk to a doctor or pharmacist before starting or stopping any supplement.