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I HEARD IT THROUGH THE GRAPE VINE

Cardiovascular disease (CVD) claims the lives of many North Americans every year.  There are a number of ways in which individuals can reduce their risk of heart disease, including consuming red wine and purple grapes. The French have been noted for their low incidence of cardiovascular disease which has largely been attributed to their low intake of saturated fat and high consumption of fruits, vegetables and red wine.  However, while alcoholic grape beverages are known for contributing to heart disease prevention, many studies have concluded that non-alcoholic commercial grape beverages (such as Welch’s Grape Juice) and purple grapes themselves, actually possess many of the same characteristics that wine does for reducing the incidence of heart disease.

What is so unique about purple grapes?

Purple grapes and grape products, and in particular those products that are made from the skins, seeds and stems of concord grapes, are high in polyphenolic compounds. Polyphenolic compounds, such as flavonoids, are powerful antioxidants. Antioxidants are compounds that play a major role in the protection of cells from the damaging effects of oxygen and free radicals. If there are not enough antioxidants to destroy reactive oxygen in the body it can result in oxidative stress, ultimately impacting one’s risk of disease. The following describes 5 major ways that the Flavonoid antioxidants have been found to have heart health benefits:

1.      Flavonoids play a major role in reducing oxidative stress by reducing free-radical damage to the cardiovascular system. Free radicals can cause damage to lipids, proteins and nucleic acids, which can have implications for causing a number of diseases including cancer and arteriosclerosis. Flavonoids can effectively neutralize these free radicals to prevent damage to cells in the body.

2.      Flavonoids are also effective in increasing other antioxidant activities in the body, in particular, alpha-tocopherol (a vitamin E derivative). Alpha-tocopherol is known for its powerful antioxidant properties, scavenging free radicals to protect against clot formation.

3.      Flavonoids can reduce platelet aggregation by decreasing the tendency for platelets sticking together and forming dangerous clots.

4.      Flavonoids also appear to have an impact on the release of Nitric Oxide. Nitric Oxide is released in the body from stimulated platelets and can effectively inhibit platelet recruitment and thrombosis formation.

5.      Lastly, flavonoids play a role in slowing the production of oxidized LDL cholesterol (“bad” cholesterol), which is known for its contribution to blocking arteries through the formation of plaque.

Are purple grape juice and purple grape products the best source of polyphenolic compounds?

Besides wine and non-alcoholic grape beverages, citrus fruit juices also contain different classes of the polyphenolic compounds. However, a number of studies have found that citrus fruits had no effect on reducing platelet aggregation. Purple grape juice consistently demonstrated that it has a more potent effect on platelet inhibition. In addition, the concentration of polyphenolic compounds were approximately 3 times that of citrus fruit juices. Overall, this indicates that grapes and grape juice products have a higher cardiovascular preventative effect versus citrus fruit juices.

In conclusion, purple grape juice is an excellent alternative to red wine, contributing many of the same benefits for cardiovascular disease prevention. However, it is important to always look at labels when purchasing your grape juice. Ideally, the product should be low in added sugars and made from purple grapes.  The benefit comes from the purple grape not all the extras some commercial products add.

Bottom Line:  For a healthier heart, add purple grape juice to smoothies, muffins, pies, jellies and popsicles!