How cranberry juice fights bacteria that cause urinary tract infections

Scientists reported new evidence on the effectiveness of that old folk remedy &' cranberry juice &' for urinary tract infections at the ACS' 240th National Meeting. "A number of controlled clinical trials &' these are carefully designed and conducted scientific studies done in humans &' have concluded that cranberry juice really is effective for preventing urinary tract infections," said Terri Anne Camesano, Ph.D., who led the study. "That has important implications, considering the size of the problem and the health care costs involved."

Estimates suggest that urinary tract infections (UTIs) account for about 8 million medical visits each year, at a total cost of more than $1.6 billion. Camesano, who is with the Worcester Polytechnic Institute, said the study set out to shed light on how cranberry juice fights E. coli, the most common cause of UTIs. The study involved growing strains of E. coli in urine collected from healthy volunteers before and after consumption of cranberry juice cocktail. The scientists then tested the E. coli for their ability to stick together and form biofilms. Biofilms are thin, slimy layers that provide an environment for bacteria to thrive.

The scientists concluded that cranberry juice cocktail prevents E. coli from sticking to other bacteria and the surface of a plastic petri dish. E. coli that doesn't stick has a better chance of being flushed out of the urinary track. The results suggest that the beneficial substances in cranberry juice could reach the urinary tract and prevent bacterial adhesion within 8 hours after consumption of cranberry juice.