Grape juice -- with its rich, satisfying taste and vivid color -- is more than just a refreshing summer beverage or a sensible, alcohol-free alternative to red wine. Clinical studies suggest that grape juice contains flavonoids that may play a role in preventing blood from forming dangerous clots, thereby helping reduce the risk of cardiovascular disease. The studies were performed using purple grape juice made from Concord grapes; paler varieties of grape juice, although still healthy, don't provide the same benefits.
Features
Grapes -- botanically known as Vitis vinifera -- are the fruit of a deciduous, climbing vine that features clusters of pale, green flowers and roughly heart-shaped leaves. Indigenous to southern Europe and western Asia, grapes are presently grown in temperate areas worldwide. Historians believe grapes were domesticated some time before 5000 B.C. in western Asia; the first record of their use by humans dates back to 2375 B.C. Grapes -- mentioned numerous times in the Bible -- have been used not only as an important source of food and drink but also as a folk remedy for a myriad of illnesses, including liver and kidney disease, varicose veins, gangrene, hemorrhoids, tuberculosis and cancer.
Constituents
Grapes contain tannins, sugars, and citric and lactic acids. They are also rich in pectin, which is a soluble fiber that is beneficial for digestion, as well as the antioxidant vitamins A and C. The minerals potassium and chromium are also present in grapes, as is the amino acid arginine. Red and purple grapes contain anthocyanins -- plant pigments also found in blackberries and blueberries -- as well as resveratrol, a polyphenol produced in the skin of the grape to fight bacterial and fungal infections.
Effects
Drugs.com, which provides peer-reviewed medical information to consumers, reports that the flavonoids in grape juice promote healthy cardiovascular function by reducing the aggregation -- or stickiness -- of platelets in the blood, thereby helping to prevent blood clots and atherosclerosis. Unlike aspirin, which also reduces aggregation, flavonoids aren't hindered by adrenaline in the body; this trait allows them to retain their healthful effects even in times of stress. In addition, purple grape juice may prevent blood clots and heart disease by slowing the oxidation of harmful LDL cholesterol, as well as by increasing the production of nitric oxide. According to Mayo Clinic, grape juice's relaxant effect on blood vessels also promotes cardiovascular health.
Research
In a clinical study published in 2000 in "Journal of Nutrition," researchers found that grape juice was a potent inhibitor of platelet aggregation; citrus juices -- also evaluated in the study -- had no effect. The team concluded that drinking grape juice could decrease the risk of coronary thrombosis and myocardial infarction.
In an article published in 2002 in "Advances in Experimental Medicine and Biology," J.D. Folts, of the Coronary Thrombosis Research Laboratory at University of Wisconsin Medical School, noted that flavonoids in purple grape juice and red wine improved endothelial function in patients with coronary artery disease. Noting the potential to inhibit atherosclerosis, Folts called for moderate amounts of red wine or purple grape juice to be included in the daily diet recommended by the American Heart Association to help reduce the risk of developing cardiovascular disease.
References
- Drugs.com: Complete Grape Juice Information
- Mayo Clinic; Does Grape Juice Offer The Same Heart Benefits As Red Wine?; Martha Grogan, M.D.
- "Journal of Nutrition"; Grape Juice, But Not Orange Juice, Inhibits Human Platelet Aggregation; J.G. Keevil et al.; January 2000
- "Advances in Experimental Medicine and Biology"; Potential Health Benefits From The Flavonoids In Grape Products On Vascular Disease; J.D. Folts; 2002
