Cranberries and Urinary Tract Infections
Urinary Tract Infections are very common. Some women are prone to frequent UTI, having more than two in a year. In such cases, the standard medical treatment is to prescribe low-dose antibiotic prophylaxis to disrupt the bacteria. A major concern with this treatment model is the risk of bacteria developing resistance to the drug therapy.
Another treatment option that has been used for many, many years is cranberry juice. Researchers have looked at some of the ingredients in cranberry juice, trying to determine what might be the protective element. Type A proanthocyanadins (PAC) seem to coat the bladder and keep the bacteria from adhering to the inside walls. Two well conducted research studies determined that cranberry juice reduced the risk of recurrence by 39% (1)
In a interesting study (2), researchers compared two different types antibiotics versus tablets of PAC, the active ingredient in cranberry juice. The results were pretty clear, the antibiotics beat the PAC in there ability to reduce recurring bladder infections, but there was an increased risk of bacteria resistance. There was no resistance shown with the cranberry treatment.
The thing worth noting in this study is the dose of the cranberry capsule. The dosage was only 9.1 mg of PAC. Research published in the journal BMC Infectious Diseases finds that 72 mg of PACs prevent bacteria from adhering to the urinary tract lining. This is much higher than the 9.1 milligrams used in this study. I’m not suggesting that the drug companies designed the study to make sure their products beat the cranberries, but it certainly does suggest that another look at cranberry juice is in order. In the meantime, drinking plenty of cranberry juice is still a good idea.
Dr. Andrew White
St George Chiropractor
1. Howell AB, Botto Jepson RG, Mihaljevic L, Craig J. Cranberries for preventing urinary tract infections. Cochrane Database Syst Rev. 2004;CD001321.
2. H, Combescure C, et al. Dosage effect on uropathogenic Escherichia coli anti-adhesion activity in urine following consumption of cranberry powder standardized for proanthocyanidin content: a multicentric randomized double blind study. BMC Infect Dis. 2010;10:94.