It’s important to have a consistent amount of vitamin K in your diet (if on warfarin). If you have little vitamin K in your diet, a sudden spike can increase your risk of bleeding.

Resistance to oral anticoagulants has been associated with high vit K food intake.

olestra, are fortified with 80 mcg of vitamin K per each one ounce serving

Consumption of large amounts of mango fruit has been associated with enhanced effects of warfarin. The exact mechanism of interaction is unknown but may be related to the vitamin A content, which may inhibit metabolism of warfarin.

May increase INR (limited data): Grapefruit, grapefruit juice, or grapefruit seed extract, pomegranate juice.

Cranberry juice resulting in changes in the INR and/or bleeding complications (limited data).

Black currant juice and black currant seed oil may theoretically increase the risk of bleeding

An interaction with chewing tobacco was suspected in a case of warfarin therapy failure in a young male who was treated with up to 25 to 30 mg/day for 4.5 years. The inability to achieve adequate INR values led to eventual discontinuation of the chewing tobacco, which resulted in an INR increase from 1.1 to 2.3 in six days. The authors attributed the interaction to the relatively high vitamin K content in smokeless tobacco.

Some experts recommend that continuous enteral nutrition should be interrupted for one hour before and one hour after administration of the anticoagulant dose and that enteral formulas containing soy protein should be avoided. Anticouglant users should consider limiting the consumption of cranberry juice or other cranberry formulas or pomegranate juice, black currant juice, and black currant seed oil.

Nattokinase..more information

Vitamin D3 – reduce vitamin K..more information

Take Magnesium/Zinc/Iron at least two hours apart from Warfarin That should eliminate any possible interaction

Multivitamin Supplements May Affect Warfarin Anticoagulation in Susceptible Patients – PubMed

Warfarin-induced Artery Calcification Is Accelerated by Growth and Vitamin D – PubMed

Inappropriate combination of warfarin and aspirin

Comparison of Oral Anticoagulants

Complementary  and Alternative Medicine – Penn State Hershey Medical Center – Red yeast rice

Penn State Hershey Medical Center
Adverse reactions to dietary supplements containing red yeast rice: assessment of cases from the Italian surveillance system

Trans-Resveratrol Enhances the Anticoagulant Activity of Warfarin in a Mouse Model
The effects of fasting in Muslim patients taking warfarin – Lai – 2014 – Journal of Thrombosis and Haemostasis – Wiley Online Library
Over-the-counter Vitamin K1-containing Multivitamin Supplements Disrupt Warfarin Anticoagulation in Vitamin K1-depleted Patients. A Prospective, Controlled Trial – PubMed