More cranberry is more powerful against urinary infections
bladder infections, according to preliminary research, providing
further evidence of juice's health benefits.
In a small study, researchers from the University of Washington found that drinking eight ounces of the juice works better than four in combating the bacteria that cause most urinary tract infections (UTI).
The team collected urine from three volunteers before and four to six hours after consumption of 27-per cent cranberry juice cocktail. E. coli bacteria (the most common cause of UTI) were incubated in the urine samples and combined with human bladder cells.
The amount of bacteria sticking to the bladder cells was significantly reduced after the bacteria were incubated in urine from women who drank the cranberry juice cocktail, and that effect was two-fold greater after eight ounces of cranberry juice cocktail was consumed than after four ounces was consumed, they reported at the Annual Meeting of the Infectious Diseases Society of America (IDSA).
Consumers in the US are increasingly aware of the benefits of cranberry juice for urinary tract infections but in Europe, where the juice is not well known in many regions, marketers have had to work hard to promote the health benefits of the drink.
Gika, which distributes Ocean Spray products in France, claims that the number of doctors appointments for urinary tract infections is 2.5 times more in France than in the US. Recurrent cystitis affects 2 million women annually and prompts around 5 million calls to doctors.
The French food authority AFSSA has however approved the world's first health claim for the fruit and its effect on urinary tract health.
The US National Center for Complementary and Alternative Medicine of the National Institutes of Health is further investigating the length of time that the antibacterial activity of cranberry juice lasts, the magnitude of activity with additional doses, and the effects of concurrent food ingestion.
It is thought that a specific type of tannin found only in cranberries and blueberries interacts with the little projections on the E. coli preventing them from sticking to the walls of the bladder and causing infection.
"The next step is to evaluate our findings in a larger group of women, and then conduct a trial to help determine if the laboratory findings translate into clinical differences in the rate of UTI depending on the dosage of cranberry consumed," said Dr Kalpana Gupta, principal investigator of the University of Washington study.
