Dr Khalid Rhaman and colleagues from a nutraceutical research group at Liverpool John Moores University have previously demonstrated in a clinical trial that a daily supplement of Kyolic brand aged garlic extract inhibits platelet aggregation in healthy people.
In a second trial reported two years ago they showed that it also reduces oxidative stress in smokers, people at high risk of heart disease.
"Cardiovascular disease has so many factors. We are trying to see if garlic can affect each of these," Dr Rahman told NutraIngredients.com.
"We have found that aged garlic extract helps platelets to become less 'sticky' hence decreasing the chances of a clot formation," he added.
Dr Rahman's team is now investigating the mechanism behind the extract's impact on platelet aggregation to support its use as a preventative measure by heart patients.
"We already have an idea about the mechanism. We think it may affect the pathway that is also targeted by aspirin. But most likely it is probably doing something to the receptors on the platelets, perhaps changing them or covering them somehow, which would stop the molecules that lead to aggregation from binding to them," he said.
If the new clinical trial, planned to start in February, confirms a mechanism for the inhibition of platelet aggregation, the findings would offer significant support for use of aged garlic extract to help prevent heart attacks by reducing the chances of blood clots forming.
These clots can be fatal as blood vessels surrounding the heart can become blocked, causing parts of the heart to die because of lack of blood.
Dr Rahman is currently in the middle of an in vitro study to test the mechanism. The laboratory work has shown that different compounds in the aged garlic extract have a synergistic affect on platelet aggregation.
Unlike other garlic products that standardize the amount of allicin present, Kyolic aged garlic extract is standardized to SAC (S-Allyl Cysteine), a beneficial water-soluble sulphur containing compound. It does not contain any allicin, believed by other manufacturers to be garlic's most active compound. Kyolic producer Wakunaga maintains however that allicin is not bioavailable in the body.
Cardiovascular disease is the biggest cause of death around the world, and kills one in three people in the UK.