Final answer:
Foods and supplements that may affect blood clotting while under Warfarin include spinach and other leafy green vegetables, broccoli, kale, Brussels sprouts, and vitamin K supplements.
Step-by-step explanation:
Vitamin K is necessary for proper blood clotting, and Warfarin is a medication that works by interfering with the action of vitamin K, which in turn inhibits the clotting process. Foods and supplements that are rich in vitamin K can counteract the effect of Warfarin and affect blood clotting. Some examples of foods and supplements that may affect blood clotting while under Warfarin include spinach and other leafy green vegetables, broccoli, kale, Brussels sprouts, and vitamin K supplements.