Cranberry juice now unlikely to prevent cystitis

October 16, 2012, Wiley

Cranberry juice is unlikely to prevent bladder and kidney infections, according to an updated systematic review published in The Cochrane Library. The authors analysed the most up-to-date evidence and concluded that any benefit, if present at all, is likely to be small and only for women with recurrent UTI.

(UTIs) affect the , as in , and sometimes the kidneys. Cranberries and cranberry juice have been used to prevent UTIs for decades, although it is not clear how they might help protect against infection. According to one theory, certain sugars and flavanol in cranberries prevent bacteria sticking to cells lining the walls of the urinary tract. Several systematic reviews have been published on the subject in The , each time incorporating more evidence. In the last review in 2008, it was concluded that cranberries offer a small benefit in preventing recurring UTIs in women.

In the current review, the researchers gathered together evidence from 24 studies that involved a total of 4,473 people. These studies included 14 added since the 2008 update. Those in treatment groups were given cranberry juice, tablets or capsules, while those in control groups were given placebo cranberry products, water, methenamine hippurate, , or nothing. Although in some studies there were small benefits for women suffering from recurring infections, women would have to consume two glasses of cranberry juice per day for long periods to prevent one infection. The researchers conclude that current evidence does not support cranberry juice as a means of preventing UTIs.

"Now that we've updated our review with more studies, the results suggest that cranberry juice is even less effective at preventing UTIs than was shown in the last update," said lead researcher Ruth Jepson of the University of Stirling in Stirling, UK. In the studies where participants were given juice, there were large numbers of drop-outs, suggesting it might not be acceptable to drink over long time periods. A common problem with the studies evaluating cranberry tablets or capsules was that they rarely reported the amount of active ingredient, so it was unclear whether levels would have been high enough to have any effect.

"We can't see a particular need for more studies of the effect of cranberry juice, as the majority of existing studies indicate that the benefit is small at best, and the studies have high drop-out rates," said Jepson. "More studies of other cranberry products such as tablets and capsules may be justified, but only for women with recurrent UTIs, and only if these products contain the recommended amount of active ingredient."

Explore further: Cranberry products associated with prevention of urinary tract infections

More information: Jepson RG, Williams G, Craig JC. Cranberries for preventing urinary tract infections. Cochrane Database of Systematic Reviews 2012, Issue 10. Art. No.: CD001321. DOI: 10.1002/14651858.CD001321.pub5

Related Stories

Cranberry products associated with prevention of urinary tract infections

July 9, 2012
Use of cranberry-containing products appears to be associated with prevention of urinary tract infections in some individuals, according to a study that reviewed the available medical literature and was published by Archives ...

Recommended for you

Who uses phone apps to track sleep habits? Mostly the healthy and wealthy in US

January 16, 2018
The profile of most Americans who use popular mobile phone apps that track sleep habits is that they are relatively affluent, claim to eat well, and say they are in good health, even if some of them tend to smoke.

Improvements in mortality rates are slowed by rise in obesity in the United States

January 15, 2018
With countless medical advances and efforts to curb smoking, one might expect that life expectancy in the United States would improve. Yet according to recent studies, there's been a reduction in the rate of improvement in ...

Teens likely to crave junk food after watching TV ads

January 15, 2018
Teenagers who watch more than three hours of commercial TV a day are more likely to eat hundreds of extra junk food snacks, according to a report by Cancer Research UK.

Can muesli help against arthritis?

January 15, 2018
It is well known that healthy eating increases a general sense of wellbeing. Researchers at Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) have now discovered that a fibre-rich diet can have a positive influence ...

Your dishwasher is not as sterile as you think

January 13, 2018
(HealthDay)—Your dishwasher may get those plates spotless, but it is also probably teeming with bacteria and fungus, a new study suggests.

Study reveals what sleep talkers have to say

January 12, 2018
A team of researchers with members from several institutions in France has conducted a study regarding sleep talking and has found that most sleep talking is not only negative in nature, but involves a large amount of swearing. ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.