Garlic is an herb that is best known as a flavoring for foods, but has also been used a supplement or a medication to treat a variety of conditions. According to MedlinePlus, garlic has known antifungal properties and has been effective in the prevention and treatment of high blood pressure and atherosclerosis, or hardening of the arteries. Scientists have determined that high intake of garlic will reduce the number of tick bites you may experience and reduce your potential for certain cancers. However, the effect that garlic has on your blood clotting ability is not as clearly understood.
Garlic
Garlic is a rich source of organosulfur compounds and a chemical called allicin. According to Linus Pauling Institute of Oregon State University, allicin will rapidly break down to form a variety of organosulfur compounds, which are thought to be responsible both for the distinctive odor and flavor as well as any health benefits. The method by which these compounds are active, or bioavailable, is only partially understood. Using animal studies, scientists have determined that the compounds are absorbed in the intestines, but they have not found them at the cellular level or in the blood, urine or stool of humans.
Test Tube Studies
One of the first steps in your body when a blood clot begins to form is the aggregation, or coming together, of platelets. Physicians at the Linus Pauling Institute believe that by reducing the aggregation of platelets, the risk heart attack and stroke can be reduced. In multiple studies, researchers found that garlic supplementation using raw garlic, dehydrated garlic, oil macerates or aged garlic would inhibit or stop platelet aggregation in a test tube. This is referred to as in vitro or ex vivo circumstances, meaning outside of a living organism.
Effects on the Body
In two different studies, researchers did not find the same effect on platelet aggregation when subjects consumed garlic and their blood was tested. In November 2007, research published in "Anesthesia and Analgesia" studied the administration of raw dietary garlic on 18 subjects and found that the baseline values of platelet function were not impaired by a single or repeated consumption of raw dietary garlic. Similarly, research published in December 2007 in "Plastic and Reconstructive Surgery" found that the administration of herbal supplement garlic using a commercially available agent had no effect of platelet function.
Warnings
The discrepancies between studying the herb inside a test tube and in clinical human trials requires more research to state conclusively that garlic has no effect on blood clotting and is safe to be used prior to surgical procedures. According to doctors at the University of Maryland Medical Center, other side effects of using garlic include an upset stomach, bloating, bad breath, body odor and a stinging sensation on the skin if handling large amounts of raw garlic. Other rarer side effects include dizziness, headache, fatigue, loss of appetite and muscle aches. Garlic supplements may interact with blood thinning medications and protease inhibitors used for treating HIV. Before including garlic in your daily supplementation regimen, consult with your primary care physician to ensure it will have no interaction with other medications you are taking or an underlying medical condition.
References
- MedlinePlus: Garlic
- Linus Pauling Institute: Garlic
- "Anesthesia and Analgesia"; Garlic at Dietary Doses Does Not Impair Platelet Function; G Scharbert, ML Kalb, M Duris, et. al.; November 2007
- "Plastic and Reconstructive Surgery"; The Effect of Herbal Medicines on Platelet Function: An InVivo Experiment and Review of the Literature; BW Beckert, MJ Concannon, SL Henry, et al.; December 2007
- University of Maryland Medical Center: Garlic
