People who regularly drink cranberry juice or take cranberry capsules are less likely to get urinary tract infections, a new meta-analysis suggests. Researchers found cranberry products seemed especially helpful for women who had trouble with recurrent UTIs.
"What this is doing is solidifying what has been folklore for quite some time," said Dr Deborah Wing, who has studied urinary tract infections at the University of California, Irvine but wasn't involved in the new study. "Finally, the science is catching up to what our mothers have been telling us for so many decades," she said.
Still, Dr Wing noted some women have trouble drinking a lot of cranberry juice or don't like swallowing the large capsules. There's also a lack of data about what form of cranberries - juice versus capsules, for example - is easier to take and better for reducing UTI risk - and the new study doesn't answer those questions.
Dr Chih-Hung Wang from National Taiwan University Hospital and colleagues included 10 earlier studies of about 1 500 people in their meta-analysis. Most were women, and all were randomly assigned to take daily cranberry products, placebo products or nothing. The amount of cranberry compounds used in the studies varied greatly, from one-gram capsules to close to 200 grams of cranberry juice daily.
Risk of infection reduced
Overall, participants assigned to cranberry products had 38% fewer UTIs, the research team reported Monday in the Archives of Internal Medicine. For women with a history of multiple infections, the risk of UTI was reduced by 47%. Because of differences between the trials and how they were conducted, Dr Wang and colleagues said the findings "should be interpreted with great caution."
Recent evidence suggests certain compounds in cranberries - and maybe other berries as well - might prevent bacteria from attaching to tissue in the urinary tract. Cranberry tablets are also relatively cheap, starting at about 25 cents per day. However, one recent study found antibiotics were still more effective at preventing infections in Dutch women with recurrent UTIs.
(Reuters Health, Genevra Pittman, July 2012)