By Donald J. Brown, ND
Healthnotes Newswire — Regular consumption of cranberry juice appears to be an effective tool to prevent the recurrence of urinary tract infections (UTIs) in women, according to a study recently published in the British medical journal BMJ.1
One hundred and fifty women with acute UTIs caused by the bacteria Escherichia coli (E. coli) were treated with antibiotics to resolve the infection. They were then placed in one of three groups assigned to take: (1) 50 ml of a cranberry juice concentrate (that also contained lingonberry) that was consumed five times per week for six months; (2) 100 ml of a lactobacillus drink (containing the beneficial bacterium Lactobacillus GG) consumed five times per week for one year; or (3) no treatment. The cranberry juice concentrate was prepared by adding 200 ml of water.
After six months, only eight women (16%) taking cranberry juice experienced a recurrence of a UTI compared to 19 (39%) in the lactobacillus group and 18 (36%) in the no-treatment group. Interestingly, even though women in the cranberry group stopped consuming the juice after six months, they had a lower rate of UTI recurrence at 12 months as well.
Prevention of UTIs in women is a major health issue. Up to 60% of women have a UTI at some point in their life and at least a third of them experience a recurrence during the following year.2 Recurrence of UTIs is most common in women 25–29 years of age and in those over 55. In the United States, over 11 million women receive antibiotics for UTIs each year at a cost of about $1.6 billion.3 Repeated use of antibiotics leads to resistant bacterial strains and greater chance of recurrence in some women.
Cranberry, consumed either as juice or as a dried powder in capsules, offers women a safer and less expensive alternative for prevention of UTI recurrence. One small clinical trial found that a powdered cranberry concentrate in capsules effectively prevented recurrence of UTIs in young women.4 In another study, regular consumption of cranberry juice reduced levels of bacteria such as E. coli in the urine of elderly women at risk for UTIs.5 Further clinical trials are needed to determine the optimal form and amount of cranberry to prevent UTIs in women.
The choice of a lactobacillus drink as a comparison to cranberry in this study is puzzling. Currently, there is no published evidence that oral consumption of lactobacilli will prevent UTIs. However, direct application of lactobacillus preparations into the vagina has been found to reduce the recurrence of UTIs.6
References1. Kontiokari T, Sundqvist K, Nuutinen M, et al. Randomized trial of cranberry-lingonberry juice and Lactobacillus GG drink for the prevention of urinary tract infections in women. BMJ 2001;322:1–5.
2. Ikäheimo R, Siitonen A, Heiskanen T, et al. Recurrence of urinary tract infection in a primary care setting: analysis of a 1-year follow-up of 179 women. Clin Infect Dis 1996;22:91–9.
3. Foxman B, Barlow R, D’Arcy H, et al. Urinary tract infection: self-reported incidence and associated costs. Ann Epidemiol 2000;10:509–15.
4. Walker EB, Barney DP, Mickelsen JN, et al. Cranberry concentrate: UTI prophylaxis. J Family Pract 1997;45:167–8 [letter].
5. Avorn J, Monane M, Gurwitz JH, et al. Reduction of bacteriuria and pyuria after ingestion of cranberry juice. JAMA 1994;271:751–4.
6. Bruce AW, Reid G. Intravaginal instillation of lactobacilli for prevention of recurrent urinary tract infections. Can J Microbiol 1998;34:339–43. Donald J. Brown, ND, is a naturopathic physician and one of the leading authorities in the United States on evidence-based herbal medicine. He is the founder and director of Natural Products Research Consultants, Inc., and serves on the Advisory Board of the American Botanical Council and the President's Advisory Board of Bastyr University.