What it does
Vitamin K1 is abundant in plant foods, especially leafy greens. Vitamin K2 refers to several menaquinones found in some animal and fermented foods and produced by bacteria.
Food sources and absorption
Kale, spinach, collards, broccoli, Brussels sprouts, and vegetable oils are useful sources. Eating vegetables for vitamin K does not make them unhealthy for people on anticoagulants.
Safety and individual context
Warfarin dosing is sensitive to vitamin K intake. The goal is usually consistency rather than avoiding all vitamin-K-rich food, but medication management must come from the prescribing clinician or anticoagulation team.
Primary reference
NIH Office of Dietary Supplements consumer fact sheet
How to use this information
Reference values describe population needs and are not a diagnosis. Food patterns, health conditions, pregnancy, laboratory results, and medications can change what is appropriate. Avoid high-dose supplementation unless there is a clear reason and qualified guidance.