Garlic, a pungent spice used to enliven many food dishes, has a long history of medicinal use to treat everything from the common cold to cancer. Garlic may also play a part in protecting against heart disease by its effect on platelets, irregularly shaped cell fragments that are the smallest of the blood cells, according to the University of Oklahoma Health Sciences Center. Platelets clump together at the site of injury to help stop bleeding. Taking garlic doesn't produce more platelets, but it does decrease platelet aggregation, the ability to stick together.
Garlic's Actions on Platelets
Laboratory studies show that garlic has multiple actions that inhibit platelets from sticking together. Garlic inhibits formation of thromboxane A2, a compound that binds to platelets and activates their clotting actions. Taking garlic can also decrease the ability of platelets to bind with fibrinogen, a protein that helps to form blood clots to seal off bleeding blood vessels. Garlic does not increase platelet production in the bone marrow.
Platelet aggregation plays a role in the development of stroke and heart disease. Build up of plaque, cholesterol and debris deposits in the walls of blood vessels can damage the blood vessels. Platelets stick to the injured blood vessels, forming blood clots that further narrow the interior of the vessel and impede blood flow. Pieces of the clots can break off and lodge in blood vessels that supply the brain with blood, causing a stroke. Because garlic reduces platelet aggregation, clots are less likely to form. Since fewer platelets stick to damaged areas, more platelets circulate in the blood.
Garlic and the Platelet Count
Garlic doesn't helps your body make more platelets, but it does prevent platelets from sticking together. A normal platelet count ranges from 150,000 to 400,000 units per liter. If you have a very high platelet count, you may have an increased risk of platelet aggregation; taking garlic may help to reduce the blood's ability to form clots.
If you have an abnormally low platelet count, you may have an increased tendency to bleed from minor injuries or even when you haven't injured yourself at all. Do not take garlic to build up your platelet count, because it can increase your tendency to bleed, worsening the problem, and it will not increase your platelet count. If you take blood thinning medications, garlic could potentiate their effects, the University of Maryland Medical Center warns. If you have any type of platelet disorder, ask your doctor before taking garlic.