Foods rich in flavanols include berries ... the researchers pointed to a specific flavanol called quercetin. It is produced in red grapes as they are exposed to sunlight. Quercetin impedes ...

In this case, other foods that contain quercetin are not ... be to give human subjects two red wines that are low and high in quercetin and ask whether either wine causes a headache.

The GI is a measure of how food affects the rise ... heart health when consumed in high amounts. Apples are a good source of several antioxidants, including quercetin, catechin, and chlorogenic ...