Grape juice might be protective against heart disease, similar to the effect of red wine. Researchers from the Universite Louis Pasteur de Strasbourg examined the effect of grape juice on the heart. They found that grape juice could have a similar effect (against heart disease) as red wine, even without the alcohol. Red wine and certain types of grape juice have high levels of polyphenols, which block the production of a protein linked to cardiovascular disease - the number one killer in many Western countries. Heart and vascular problems develop when endothelial cells that make up blood vessels do not work properly. The researchers found that polyphenols in grape juice activate endothelial cells to produce nitric oxide, which helps to protect against cardiovascular disease and to maintain healthy blood vessels and blood pressure. Polyphenols work the same way in red wine and in grape juice. But not every grape juice has the beneficial effect. It has to have a high level of polyphenols. The amount of polyphenols in grape juice, as in red wine, depends on the type of grape used and how it is processed. The researchers had information on more than 100 different kinds of wine and the amount of polyphenols, and it is known that the most protective ones have the highest levels of polyphenols. But little information is available on the levels of polyphenols in grape juice. The scientists are planning a further study to see whether grape juice has a similar impact on blood vessels that show signs of cardiovascular disease.
Cardiovascular Research,
February 2007