Hawthorn tea has been one of the most popular herbal teas for many generations. Hawthorn may have a positive effect on heart function by reducing blood pressure and by increasing circulation within the blood vessels. Hawthorn tea is packed with many different beneficial antioxidants that help to reduce the damage caused by free radicals within the body. This tea is also a rich source of vitamin C which is a potent immune booster that aids and strengthens the immune system.