Ask the Doctor
Questions about kidney disease? Risk factors? Signs and symptoms? Are you concerned about yourself, a friend or family member? Ask Dr. Spry.
New York, NY
January 20, 1999
For years, cranberry juice has been believed to help ward off urinary tract infections (UTIs). However, the exact reasons for this effect were not understood. A recent study offers some new clues as to why cranberry juice helps.
The benefits seem to be due to the presence in the juice of a concentrated amount of tannins, which prevent E.coli bacteria from sticking to the cells that line the urinary tract. The researchers believe the tannins do this by blocking the growth of structures the bacteria use to adhere to the walls of the bladder and other parts of the urinary tract. Among other foods they tested, blueberries were also found to contain concentrated tannins. So if you're fresh out of cranberries, try their blue cousin. For more information and a free brochure on UTIs call the National Kidney Foundation at (800)622-9010.