Written by Greg Arnold, DC, CSCS. Use of cranberry led to a 73% decrease in the number of E. Coli cells binding to the bladder tissue thus reducing urinary tract infections.
As the second most common type of infection in the body, urinary tract infections (UTIs) are particularly common in women, the elderly, and infants. The National Institutes of Health estimates that UTIs affect over 11 million American women per year. One in three women will have at least one UTI in her lifetime, leading to 11.3 million women per year affected in the U.S. alone (1) and resulting in a cost to our healthcare of more than $1 billion per year (2).
UTIs are most commonly caused by a bacteria caused E. Coli and are usually treated with antibiotics. But because the body is able to build resistance to antibiotics, interest in alternative treatment methods for UTIs continues to grow (3). The most popular alternative treatment for UTIs has been taking cranberry products (4, 5). Despite the success of cranberry to help treat UTIs, the exact way this is done is still not definitively known, although two proposed mechanisms are cranberry’s acidity (6) or compounds in cranberry that help prevent bacteria from binding to the bladder tissue (7).
Now a new study (8) has shed more light on just how cranberry helps treat UTIs. Researchers focused on compounds in cranberry called proanthocyanidins (PACs) and how they affect the ability of E. Coli to bind to bladder tissue with hair-like cells called P-fimbrae. They found that cranberry juice directly affected the P-fimbrae of E. Coli by increasing the amount of energy needed to attach to the bladder cells. This led to a 73% decrease in the number of E. Coli cells binding to the bladder tissue when cranberry was used.
If the bacteria need more energy to attach, the likelihood that they will do so diminishes and the risk of infection decreases. What’s more, the cranberry had no effect on bacteria without P-fimbrae, which includes the “good” bacteria that keep us healthy (such as the bacteria found in yogurt).
For the researchers, “These results help [explain] how cranberry products can be used to prevent bacterial attachment to host tissue and may lead to the development of better therapies based on natural products.”
Source: Liu, Yatao, et al. “Cranberry changes the physicochemical surface properties of E. coli and adhesion with uroepithelial cells.” Colloids and Surfaces B: Biointerfaces 65.1 (2008): 35-42.
Copyright © 2008 Elsevier B.V. All rights reserved.
Posted March 19, 2009.
Greg Arnold is a Chiropractic Physician practicing in Danville, CA.
References:
- B. Foxman, R. Barlow, H. D’Arcy, B. Gillespie and J.D. Sobel, Ann. Epidemiol. 10 (2000), pp. 509–515.
- “Urinary Tract Infection” posted on the University of Michigan Health System website.
- J.R. Johnson, Inf. Dis. Clin. N. Am. 17 (2003), pp. 261–278 viii.
- L. Stothers, Can. J. Urol. 9 (2002), pp. 1558–1562.
- T. Kontiokari, K. Sundqvist, M. Nuutinen, T. Pokka, M. Koskela and M. Uhari, Br. Med. J. 322 (2001), p. 1571.
- N.R.L. Blatherwick and M. Louisa, J. Biol. Chem. 57 (1923), pp. 815–818.
- K. Gupta, M.Y. Chou, A. Howell, C. Wobbe, R. Grady and A.E. Stapleton, J. Urol. 177 (2007), pp. 2357–2360.
- Liu Y. Cranberry changes the physicochemical surface properties of E. coli and adhesion with uroepithelial cells. Colloids and Surfaces B: Biointerfaces 2009; 65(1): 35-42.