Hawthorn contains many substances that may benefit the heart. These antioxidant flavonoids, including OPCs, may help dilate blood vessels, improve blood flow, and protect blood vessels from damage.

The berries, leaves, and flowers of the hawthorn plant have been used for medicinal purposes. Most modern preparations use the leaves and flowers, which are believed to contain more flavonoids than the berries.

Hawthorn is used to help protect against heart disease and help control high blood pressure and high cholesterol. Both animal and human studies suggest hawthorn increases coronary artery blood flow, improves circulation, and lowers blood pressure. It has also been used on the skin to treat boils and skin sores.