Garlic's unparalleled taste -- and its health benefits -- are heralded in two new guidesFindings that garlic fights infection and heart disease have led to an explosion in its popularity -- and in the production of supplements that offer all the benefits of garlic without its odor. But how does garlic work? Is there an optimal dose? Does taking too much cause any side effects?Many cultures have benefited from garlic's healing powers for centuries, but Americans are just beginning to explore its medicinal properties. Garlic reduces blood pressure, aids circulation, and prevents stroke. Stephen Fulder describes the most effective ways to use the "stinking rose".