Can Probiotics or Cranberry Stop Urinary Tract Infections?

What’s the real deal with these complementary and alternative practices?


scientific background, seamless pattern with bacteria, viruses and worms The term complementary and alternative medicine (CAM) refers to treatment practices that are not currently considered an integral part of conventional allopathic medical practice. Treatments are considered complementary when used in addition to conventional therapies and are considered as alternative when used instead of conventional therapies. Using probiotics or cranberry supplements alone to treat urinary tract infections is applying CAM.

A number of factors are likely fueling the increasing interest in CAM. First, traditional medical therapies for many conditions offer only marginal efficacy. In many countries, including the U.S., prescription medication insurance coverage for many “quality of life” conditions is decreasing. Also, perhaps related to concerns regarding the safety of prescription medications, there appears to be a growing desire among patients for more holistic and “natural” treatment options.

Probiotics, the good bacteria

Probiotics are bacteria in the body that are beneficial to one’s health. Probiotics are “good bacteria,” and though primarily thought of as aiding in the digestive system, probiotics are active in many parts of the body, including the vagina.

One area where probiotics have been studied is in women with recurrent urinary tract infections (UTIs). A UTI results from the transmission of pathogens from the rectum and/or vagina to the urethra and bladder. Lactobacillus is recognized as an important part of the normal flora in the female genitourinary tract and the reduction in numbers increases the risk of UTI.

Among the four randomized controlled trials involving treatment of UTI with the lactobacillus probiotic, one reported a 73 percent reduction in episodes of recurrent UTI compared with the previous year. In that trial the control group had six UTIs per patient per year versus 1.3 UTIs per patient per year after intravaginal administration of probiotics.

The other three trials showed that probiotics conferred no benefits. However, they had used various different strains of bacteria and may not have enrolled enough subjects to show a true difference.

Hydrogen peroxide producing lactobacilli are believed to be important in conferring protection from urinary tract infections. A study of 290 subjects showed that females colonized by such lactobacilli, vaginally and rectally, had a reduced risk of vaginal infection. This is one reason why hydrogen peroxide producing L. reuteri RC-14 was added to L. rhamnosus GR-1 to make a combination therapeutic to prevent UTI. Products like fem dophilus state that they provide a mix of the two bacteria.

Can cranberries stop UTIs?

Cranberry supplements are in the top 10 remedies sold by herbalists in the United States (90 percent of the world’s annual production of 50 million tons comes from the U.S.). Cranberry does not have a direct antimicrobial effect. Despite this, it inhibits the adhesion of E. coli bacteria to the bladder lining, thus impairing colonization and subsequent infection.

Results of a Cochrane Database meta-analysis of cranberry efficacy in the prevention of UTIs were published in 2004. All randomized or quasirandomized controlled trials of cranberry products in the prevention of UTIs in men, women and children were eligible for review.

In two good-quality randomized controlled trials, cranberry products significantly reduced the incidence of UTIs at 12 months compared with women in the control group who took a placebo. There was no significant difference in the incidence of UTIs between juice and capsule formulations.

We often recommend the tablets of cranberry to our chronic UTI patients because pure cranberry juice tastes horrible.

University of Colorado Urogynecology is a specialty women’s health practice focused on female pelvic health and surgery. Our physicians are also professors & researchers for the CU School of Medicine, one of the top-ranked medical schools in the nation.

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