Certain vitamins and herbs have anti-coagulant properties, meaning that they help to reduce or prevent blood clotting. These include vitamin B6 and vitamin E as well as herbs and foods that contain salicylates, or natural blood thinners; coumarin, a natural anti-coagulant; or that inhibit platelet aggregation. Always consult with a doctor before using anti-coagulant herbs or vitamin supplements. People with certain conditions like diabetes and those already taking prescription anti-coagulant medications like warfarin could experience potentially serious effects from taking anti-coagulant vitamins and herbs. No specific minerals have been found to possess anti-coagulant or anti-platelet properties.
Herbs with Salicylates
Salicylates are natural compounds that thin the blood by blocking the absorption of vitamin K, an essential component in the body's blood clotting function. Herbs high in salicylates include cinnamon, meadowsweet, peppermint, willow and yellow and white melilot. It also includes the Chinese herb dong quai, also known as angelica. Capsicum, contained in black pepper and cayenne pepper, has salicylates as well. The cooking herbs dill, oregano, thyme, paprika and tumeric are high in salicylates as well.
Herbs with Coumarin
Many herbs contain coumarin, the same substance that provides the active ingredient in several prescription anti-coagulant medications such as warfarin, as it has the ability to prolong the time it takes for blood to clot. When fermented, coumarins produce dicoumarol, an anti-coagulant that is also used in rat poisons to cause hemorrhaging. Herbs containing coumarins include aniseed, arnica, asafoetida, chamomille, horse chestnut, red clover and sweet woodruff.
Platelet Aggregation Inhibitors
Certain herbs prevent clotting by inhibiting the aggregation of blood cell platelets. These include bilberry, bromelain, cassia, feverfew, ginger, gingko, ginseng, licorice, motherwort and nettle. When combined with other anti-coagulation agents or medications, these platelet aggregation inhibitors can prolong bleeding time and in some cases increase bleeding profusion.
Vitamins B6 and E
A 1992 paper in "Thrombosis Research" reported that vitamin B6 inhibits platelet function, giving it an antithrombotic, or anticoagulant effect. A 1998 study on rabbits published in "Nutrition Research" further validated vitamin B6's antiocoagulation and antiplatelet activity. Vitamin E is a known antagonist of vitamin K, preventing its proper absorption and therefore blocking its coagulating effects. Researchers conflict on whether or not vitamin E supplementation can exacerbate bleeding time or otherwise interfere with anti-coagulant medications containing coumarin like warfarin. The herb grape seed is high in tocopherol, a constituent of vitamin E.
References
- "Thrombosis Research"; The In Vivo Effect In Humans Of Pyridoxal-5'-phosphate On Platelet Function And Blood Coagulation; V. van Wyk, et al.; Jun 1992
- "Nutrition Research"; The Optimal Levels Of Vitamin B6 In Platelet Function And Blood Coagulation Of Rabbits; Sue-Joan Chang, et al.; Jan 1999
- NYU Medical Center HealthWise; "Anticoagulants: Vitamin K And Your Diet"; Robin Parks; 2008
- Connective Tissue Disorder Site; "Foods That Naturally Thin The Blood"; Sandy Simmons
- DigHerbs: "Angelica" Paula Morstead
- Combining Anticoagulant Drugs With Herbal Medicines Is Risky, Report Says; Roger Dobson; Dec 2001
