Latest Developments in Cranberry Health Research

Abstract

Urinary tract health benefits have long been ascribed to the American cranberry, Vaccinium macrocarpon, through folklore. Now, a growing body of science supports this association. Current research suggests that this benefit is due to components in cranberry preventing the adhesion of certain bacteria in the urinary tract. Cranberry's relatively unique A-type proanthocyanidins were identified as the components that prevented the adhesion of P-fimbriated E. coli to uroepithelial cells using bioassay-directed fractionation techniques. Very recently, using an animal model, in vivo evidence was obtained suggesting that cranberry proanthocyanidins were absorbed and elicited this specific anti-adherence activity in urine. Recent preliminary research suggests that cranberry's microbial anti-adhesion effect may extend into the gastrointestinal tract, which may contribute to both the urinary tract health benefit as well as preventing attachment of H. pylori, the bacteria responsible for many peptic ulcers. Diets high in fruits, vegetables, and grains contribute to improving health status in a number of ways. Oxidative stress may play a role in the development of many chronic diseases, including cardiovascular diseases. Ex vivo testing indicates that cranberry flavonoids inhibit the oxidation of human LDL cholesterol, with proanthocyanidins the most active flavonoid fraction. Additionally, a diet rich in cranberry juice powder significantly reduced the total and LDL cholesterol in hypercholesteremic pigs. Cranberry appears to be a relatively unique fruit in that it may provide benefits both through microbial anti-adhesion and possibly through antioxidant mechanisms.