Raw vs. cooked garlic
As well as being a flavorful culinary ingredient, garlic is a therapeutic food. When raw garlic is chewed, beneficial compounds are released. Cooking can detstroy beneficial compounds; studies have found that even seconds of microwaving whole garlic cloves can negate active compounds. However, chopping or crushing raw garlic begins to release beneficial compounds, and these develop further if garlic sits for about minutes at room temperature.
As a general rule, the cooking method makes less of a difference than the cooking time, as the longer garlic is exposed to heat, the more active compounds are destroyed. But one study, published in the Journal of Functional Foods, found that stir-frying preserved the most beneficial compounds.