Unraveling the myth: Cranberry products prevent UTIs in women

New medical evidence shows that consuming cranberry products effectively prevents a UTI.

Drinking cranberry juice has long been a mythical prevention strategy for women who develop a urinary tract infection – and new medical evidence shows consuming cranberry products is an effective way to prevent a UTI before it gets started.

A global study looking at the benefits of cranberry products published in Cochrane Reviews has determined cranberry juice and its supplements reduce the risk of repeat symptomatic UTIs in women by more than a quarter, in children by more than half and in people susceptible to UTI following medical interventions by about 53% [1].

Cranberry juice and healthcare supplements commonly including the fruit, such as capsules and tablets, have long been promoted as a readily available solution to ward off the infection.

cranberry juice
Photograph: 5PH/Envato

Still, the most recent review in 2012, with evidence from 24 trials, showed no benefit from the products [2].

The medical scientists behind this updated review from Flinders University and The Children’s Hospital at Westmead aimed to correct these findings as an essential step in determining the effectiveness of cranberry products by looking at 50 more recent trials that included almost 9000 participants.

“This incredible result wasn’t surprising, since we are taught that more and better evidence always leads to the truth coming out.

UTIs are horrible and very common. About a third of women will experience one, “as will many elderly people and people with bladder issues from spinal cord injury or other conditions,” says the study lead author Dr Gabrielle Williams.

Flinders University epidemiologist Dr Jacqueline Stephens, a study co-author, says if the UTI persists untreated, it can move to the kidneys and cause pain and more complications, including sepsis in very severe cases, so prevention is the most effective way to reduce risks.

“Most UTIs are effectively, and pretty quickly, treated with antibiotics, sometimes as little as one dose can cure the problem. Unfortunately, in some people, UTIs keep coming back. Some healthcare providers began suggesting it to their patients without knowing if or how it works.

It was a harmless, easy option at the time. Even centuries ago, Native Americans reportedly ate cranberries for bladder problems, leading somewhat more recently to laboratory scientists exploring what it was in cranberries that helped and how it might work.

“The studies we looked at included a range of methods to determine the benefits of cranberry products. 

The vast majority compared cranberry products with a placebo or no treatment for UTI and determined drinking cranberries as a juice or taking capsules reduced the number of UTIs in women with recurrent cases, in children and in people susceptible to UTIs following medical interventions such as bladder radiotherapy.”

Furthermore, few people reported any side effects, the most common being stomach pain. In addition, it wasn’t determined whether cranberry products were more or less effective than antibiotics or probiotics at preventing further UTIs.

The data also did not indicate any benefits for older people, pregnant women or people who have trouble emptying their bladder.

As the researchers expanded the scope of their review to include the most recently available clinical data, Professor Jonathan Craig, Vice President and Executive Dean of Flinders University’s College of Medicine & Public Health, was able to demonstrate the real benefits of cranberry products.

“This is a review of the totality of the evidence; new findings might occur as new evidence emerges. In this case, the new evidence shows a very positive finding that cranberry juice can prevent UTI in susceptible people,” says Professor Craig.

“We have shown the efficacy of cranberry products for treating UTIs using all the evidence published on this topic since the mid-nineties. The earlier versions of this review didn’t have enough evidence to determine efficacy and subsequent clinical trials showed varied results. Still, in this updated review, the volume of data has shown this new finding.”

The study authors conclude that while cranberry products do help prevent UTIs in women with frequent recurrence, more studies are needed to clarify further who with UTI would benefit most from cranberry products [3].

[1] http://dx.doi.org/10.1002/14651858.CD001321.pub6
[2] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3370320/
[3] https://www.sciencedaily.com/releases/2023/04/230420080722.htm

Photograph: varyapigu/Envato
The information included in this article is for informational purposes only. The purpose of this webpage is to promote broad consumer understanding and knowledge of various health topics. It is not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of your physician or other qualified health care provider with any questions you may have regarding a medical condition or treatment and before undertaking a new health care regimen, and never disregard professional medical advice or delay in seeking it because of something you have read on this website.