In the 17th century cranberries were used to treat stomach complaints, liver disorders, blood conditions, vomiting, appetite loss, scurvy, and cancer. While Native Americans made poultices from whole dried berries for wounds, New Englanders employed cranberries in remedies for gallbladder ailments.
In the early 1920s, American scientists discovered that cranberries were an effective herbal treatment for recurrent urinary tract infections (UTIs). Researchers of that era knew that bacteria tend to flourish in an alkaline medium. Consequently, they speculated that an acid environment would kill bacteria. They found that ingesting cranberries increased acidity of urine, creating exactly the type of acid milieux in the intestines that destroyed pathogens. Further investigations revealed that hippuric acid, an active constituent in cranberry, might be responsible for the antibacterial action of cranberries.
Much of the evidence for the antibacterial properties of cranberry was initially anecdotal. Nonetheless, the popularity of cranberry juice for treating UTI and chronic kidney inflammation soared as news of its virtues spread largely by word-of-mouth. By the 1960s, however, researchers concluded that the antibacterial activity of cranberry could not be attributed to acidic urine. A reanalysis of the evidence revealed that at least one quart of cranberry juice would have to have to be consumed at one time to furnish a sufficient amount of hippuric acid to suppress bacteria.
Recent evidence has since shown that cranberry exerts antibacterial effects against the etiologic pathogens of urinary tract infections through other mechanisms. In in vitro and human clinical studies, cranberry was shown to alter the environment of the urinary tract. This renders the bladder and urethra less amenable to bacteria, particularly Escherichia coli, one of the primary bacteria responsible for UTI.
Structure-function relationships have been only partially delineated for cranberry. It contains two constituents that apparently interfere with the capacity of microorganisms to adhere to the epithelial cells lining the urinary tract. One of these active compound is fructose. The other is an unidentified polymeric compound not yet identified.
Medicinal Uses :
raditional use: Stomach complaints, liver disorders, wounds, blood conditions, vomiting, appetite loss, scurvy, and cancer; since the 1920s, it has been a popular folk medicinal treatment in the United states for bladder infections
Conditions: UTIs of the bladder and urethra
Clinical applications: Prevention and treatment of UTI
Another Name :
Cranberry (English)
Vaccinium macrocarpon (Botanical)
Ericaceae (Plant Family)
