Cranberry effective against recurrent UTIs: Meta-analysis

© iStock/Alexandra Thompson

A daily intake of cranberries may significantly reduce the risk of recurrent urinary tract infection (rUTI) in generally healthy women, says a new meta-analysis of seven randomized controlled trials.

Data from 1,498 women indicated that cranberry (Vaccinium microcarpum) intake reduced the risk of rUTI by 23%, scientists from Tufts University, Biofortis Research, and UCLA presented at the recent Experimental Biology 2017 event in Chicago.

“Limited data from subgroup analysis suggested cranberry was more effective in interventions with cranberry as a capsule or tablet,” wrote the authors in their presentation abstract, published in the FASEB Journal.

Study details

A woman has a 50% risk of getting a UTI during her lifetime, with an estimated 20–30% of these women having recurrent UTI (rUTI), explained the researchers. The annual healthcare cost of UTIs in healthy women is estimated to be over $2.6 billion.

The researchers combed the scientific literature and identified seven relevant randomized controlled trials to include in their meta-analysis.

The data revealed that, for healthy women, the risk of rUTIs was significantly reduced, with capsules and tablets suggested to be more effective.

However, the researchers noted: “Overall, studies were relatively small with only two having more than 300 subjects.

“Results suggest cranberry may be effective in preventing rUTIs in generally healthy women; however, larger high-quality studies are needed to confirm these findings,” they concluded.

Antibiotic use

In 2004 France became the first country to approve a health claim for the North American cranberry with at least 36mg of proanthocyanidins (PAC) to “help reduce the adhesion of certain E. coli bacteria to the urinary tract walls”, and subsequently fight urinary tract infections (UTIs).

The Biofortis scientists also presented data from a post-hoc analysis of an intervention trial at Experimental Biology 2017, which examined the use of antibiotics to treat UTIs in women with a recent history of these kinds of infection.

The randomized, double-blind, placebo-controlled, multicenter clinical trial included 373 women with a recent history of UTI randomly assigned to consume either 240 mL/day of a cranberry beverage or a placebo beverage for 24 weeks.

The results indicated that investigator-diagnosed episodes of clinical UTI were significantly reduced in the cranberry group, compared to placebo (39 vs. 66, respectively).

“The results of this post-hoc analysis indicate that daily consumption of a cranberry beverage reduced the incidence of antibiotic treated clinical UTI in women with a recent history of UTI,” wrote the researchers in the FASEB Journal.

This study included scientists from Midwest Biomedical Research – Center for Metabolic and Cardiovascular Health, Biofortis Innovation Services, Ocean Spray Cranberries, and Boston University School of Medicine and VA Boston Healthcare System. The study was funded by Ocean Spray Cranberries.

Sources:
FASEB Journal
Volume 31, Number 1, Supplement lb343
“An Updated Meta-Analysis of Cranberry and Recurrent Urinary Tract Infections in Women”
Authors: Z. Fu, D. Liska, D. Talan, M. Chung

FASEB Journal
April 2017, 31:964.26
“Cranberry Beverage Consumption Reduces Antibiotic Use for Clinical Urinary Tract Infection in Women with a Recent History of Urinary Tract Infection”
Authors: K.M. Nieman et al.

Related Products

See more related products