After getting a urinary tract infection (UTI), kids in Finland had fewer recurring infections over the next year when they drank cranberry juice every day in a new randomised controlled trial.
"For children who have recurrent UTIs, I think that this study provides some preliminary suggestion that...supplementing with cranberry juice could reduce the number of recurrences," said Dr Brett White, a paediatrics and family medicine specialist at Oregon Health and Science University in Portland.
"It's not super-strong evidence, but it's a possibility, and I don't think there would certainly be any harm in giving kids cranberry juice", said Dr White, who has studied the infections but wasn't involved in the new research.
The study included 255 kids aged one to 16 treated for a UTI at seven different Finnish hospitals. The youngsters were randomly split into two groups: half of them drank a cup of cranberry juice daily for six months, while the other half downed berry-free drinks instead.
Consider juice as add on preventing measure
Over the next year, a similar number of kids getting each drink – 20 out of 126 in the cranberry group and 28 of 129 non-cranberry kids – had at least one additional UTI, Dr Jarmo Salo of Oulu University Hospital and colleagues report online in Clinical Infectious Diseases.
But among kids who did have additional infections, the ones who drank daily cranberry juice had fewer total UTIs over the course of the study and spent less time taking antibiotics.
Participants on cranberry juice had 27 new infections combined and spent an average of 12 days each over the year taking antimicrobial drugs for UTIs, compared to 47 new infections in kids not prescribed cranberry and an average 18 days on antibiotics.
Dr Nader Shaikh, who has studied UTIs at Children's Hospital of Pittsburgh, said that parents of kids with recurrent UTIs should consider cranberry juice as a possible add-on preventive measure, but not as a substitute for antibiotics if they're prescribed.
Don’t overdo it parents
"If it has a chance of helping, and it looks like it does help a little bit, then a small amount of juice is okay," Dr Shaikh, who wasn't involved in the new research, told Reuters Health. "I would stick to four ounces a day. As long as parents don't overdo it, I think it's a reasonable treatment."
Dr Shaikh added that too much cranberry juice could lead to cavities and diarrhoea.
Twenty-seven kids dropped out of the study – half of them because they were reluctant to drink the juice. And in the cranberry juice group overall, kids drank less than two-thirds of the "doses" researchers gave them.
Both juices in the study were provided by Ocean Spray, which also gave the researchers a grant that partially covered other study expenses.
Juice protects bacteria
Dr White said that while little prior research has examined the effect of cranberry juice on UTIs in kids, cranberries have been shown to decrease the number of symptomatic UTIs in women.
"There is something in the cranberry fruit that specifically prevents bacteria from adhering to the walls lining the urinary bladder," he explained in an interview with Reuters Health. "One can assume that would probably apply to other populations as well, including children."
One recent study did find that cranberries weren't as good as antibiotics at preventing UTIs in women. Dr Smith and Dr Shaikh both noted that there's limited evidence that treating kids with long-term antibiotics can actually ward off the infections – but that approach probably will raise the risk of bacteria becoming resistant to the drugs.
(Reuters Health, December 2011)