In this study, the researchers collected urine samples from healthy volunteers before and after consumption of cranberry juice. They then analyzed the ability of E. coli to form biofilms in the urine. Biofilms are thin, slimy layers that provide a sort of scaffold for bacteria to thrive and multiply.
The researchers found that metabolites of cranberry juice in the urine prevented E. coli from sticking to other bacteria and thus forming harmful biofilms.
“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,” researchers say. “That has important implications, considering the size of the problem and the health care costs involved.”
The beverage used in this study consisted of cranberry juice, water, and sweeteners found in cranberry juice cocktail. UTIs are difficult to treat and affect women more than men. It is thought that they result in 8 million visits to the doctor annually and cost $1.6 billion to treat.
While it is not recommended to self-treat urinary infections, it is clear that cranberry juice may help in no small measure.