Among the nine types of odor-free garlic pills that he tested, only a few induced significant relaxation of the vessels. Those containing the most allicin caused the vessels to relax most. For instance, one product with 12.5 milligrams of allicin per gram relaxed the vessels to just 20 percent of their pre-test constriction. But two of the pills containing no allicin left the arteries at 80 to 97 percent of the original constriction. This time, he had altered some of the exposed vessel segments so that they could no longer produce nitric oxide.
Nitric oxide is a chemical that vessel walls produce to trigger arterial relaxation.
Ku now suspects that up to 70 percent of the garlic effect is due to some triggering of nitric oxide production in cells lining the interior of exposed arteries. Chop first, heat later Researchers at Pennsylvania State University have been studying garlic's potential health benefits for more than a decade. So, he and Kun Song, a graduate student, decided to put raw cloves of garlic into a microwave oven and irradiate them on high for 1 minute. However, Milner says that microwaving inactivated allicinase, the allicin-producing enzyme. It's no longer effective.