Juice Plus+ Study on Endothelial Function
In 2003, a study on Juice Plus+ by Gary D. Plotnick, MD, FACC, Mary C. Corretti, MD, FACC, Robert A. Vogel, MD, FACC, Robert Hesslink, JR, SCD, and John A. Wise, PHD was published in the Journal of the American Collegy of Cardiology (JACC). The study showed that eating Juice Plus+ for four weeks can dramatically protect the endothelial function in human arteries, thereby protecting the body from significant blood vessel constriction and loss of blood flow due to oxidation from high-fat meals. As measured in the brachial arteries, vasoactivity was reduced by as much as 40-50% after eating a high-fat meal in the placebo groups, and the Juice Plus+ groups before supplementation started.
The group eating Juice Plus+ Orchard and Garden Blends only experienced about 16.6% decrease in vasoactivity, while the group eating Juice Plus+ Orchard, Garden, and Vineyard Blends experienced a decrease in vasoactivity of only 1.7% – almost completely mitigating the effects of the high-fat meal on endothelial function and vasoactivity!
Eating a high-fat meal causes a temporary decrease in blood flow due to increased oxidative stress, as measured by flow-mediated brachial artery vasodilation. This has been known for years and is one reason why most heart attack victims have an episode shortly after eating a high-fat meal. The high-fat meals, typical of many American diets, dramatically increase oxidative stress in the arteries, damaging endothelial cells and limiting their proper functioning for up to six hours after the meal.
In healthy volunteers, four weeks of daily supplementation in the study with a fruit-and-vegetable juice concentrate (Juice Plus+), with or without an adjunctive complex phytochemical supplement, blunts the detrimental effect of a high-fat meal on blood flow in the brachial artery—even when the supplement is not administered with the meal.
Furthermore, the group taking Juice Plus+ saw increases in the combined serum nitrite/nitrate concentration. Because green leafy vegetables contain nitrates, it’s conceivable that the Juice Plus+ supplement may have contributed modestly to dietary nitrate intake, but this is unlikely to account for the magnitude of the observed increase in serum levels of NO metabolites. Because protein intake was not specifically controlled for several days before measurement, serum nitrite/nitrate levels have limited reliability. Nitric oxide is known to be the primary mediator of flow-induced brachial vasodilation (43); therefore, the favorable impact of phytochemical supplementation on endothelial function in this study seems likely to reflect preservation of NO bioactivity.
Nitric Oxide activity is important because it is what allows the endothelial cells to expand and contract blood vessels as needed to moderate blood pressure and blood flow properly. Lack of endothelial flexibility and NO has been linked to increased risk of heart disease and other cardiovascular disorders.