Researchers at the Universite Louis Pasteur found that Concord grape juice stimulated the production of nitric oxide in endothelial cells, providing a vasorelaxation effect. Nitric oxide is crucial in the body's natural system for maintaining healthy, flexible blood vessels and helps support healthy blood pressure.
They further discovered that the juice produced the relaxation effect by stimulating the same chemical reactions in the arteries that are activated by red wine.
The beneficial effect provided by Concord grape juice lasted up to six hours, whereas this extended effect has not been reported with red wine.
The research therefore suggests that the benefits of drinking Concord purple grape juice may last long after finishing the juice. The research also demonstrated that it's the components of the grape, rather than alcohol, which produce this beneficial effect for the heart.