There are many reasons why women are prone to urinary tract infections (UTIs) and there is abundant, sound advice for prevention. Traditional wisdom suggests that cranberry juice is a good treatment and preventive. Unfortunately, the medical community has found the use of cranberry juice rather than antibiotics to be controversial. A recent study compared the effectiveness of cranberry extract to the common UTI antibiotic, trimethoprim, for treatment of women with recurrent UTIs. Surprisingly, cranberry extract was found to be safer, more effective and better tolerated for chronic UTI prevention than was the common antibiotic.
Natural Bacteria are First Line of Defense against UTIs
Women tend to suffer from urinary tract infections, and this predisposition is usually attributed to a shorter urethra that is closer to the anus. The urethra is the tube running from the bladder to the outside and it is lined with cells that secrete mucus to protect the cells against the urine. Thus, the major protection against infection of the bladder, is the continuous flow of urine out of the body.
Bacteria must bind to the lining cells in order to avoid being swept into the toilet. Pathogenic bacteria that can grow in the urethra and bladder must move up the urethra to be a problem. Transit of pathogenic bacteria is normally blocked by resident, natural bacteria that already occupy positions along the urethra. Thus, a UTI requires some disruption of the normal, protective resident bacteria and pathogens.
Antibiotics Disrupt Natural Bacterial Barrier Leading to Fungal Infections
Antibiotic treatment for UTIs or other infections typically leads to disruptions of the gut flora and fungal infections. Probiotics are suggested to replace the lost bacteria until the normal bacterial communities can be reestablished. In the mean time, fungi, such as yeasts, can move in and cause annoying opportunistic infections. Vaginal thrush is one of the common complaints leading to disuse of low level antibiotics for treatment of recurrent UTIs.
Cranberry Prevents UTIs and Retains Natural Bacteria
To address the need for UTI treatment in older adults and avoid the problems of long term antibiotic use, a recent study examined cranberry extract as a preventive treatment. The study was performed at the Ninewells Hospital and Medical School at the Universigy of Dundee, Scotland, U.K. The participants were 137 women who had previously received two or more antibiotic treatments of UTIs.
For the study, half received 500 mg of cranberry extract and the other half received 100 mg of trimethoprim. Withdrawal from the study was twice as high for the antibiotic group, 12% vs. 6%. The antibiotic, trimethoprim, was slightly more effective in preventing reoccurrence of UTIs, but that advantage was lost, because of the increased tendency of antibiotic users to leave the study due to bacterial or fungal overgrowth. The researchers were surprised at the effectiveness and tolerance of the cranberry extract, and concluded that cranberry was a cheap, safe alternative to antibiotics for prevention of urinary tract infections.