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A home remedy for urinary tract infections may work for some women, research suggests.
Cranberry juice has long been espoused as a treatment for repeat urinary tract infections (UTIs) and research suggests that certain substances in the fruit can stop bacteria sticking to the lining of the bladder.
Dr Ruth Jepson at the University of Stirling in Scotland and a colleague looked at whether cranberry products can prevent repeat bouts of the infection.
Analysing 10 previous studies, they found some evidence that cranberry juice or cranberry supplements may be effective for women with recurrent UTIs.
However, the benefits for other people - including the elderly, who are at elevated risk of UTIs - were uncertain.
The findings are reported in the Cochrane Library, which is published by the Cochrane Collaboration, an international organisation that evaluates medical research.
The 10 studies in the review involved a total of 1049 adults. In some, cranberry juice was pitted against plain water or another type of juice; others tested cranberry tablets against placebo pills.
Overall, the researchers found, the cranberry products reduced recurrent UTIs by one-third over a year - though the benefit was not seen in all studies or for all groups of people.
And although women with recurrent UTIs generally seemed to benefit, it was not clear from the studies how much cranberry juice they would need to drink, or for how long, to prevent the infection.
Jepson said the patients may also need to consider the cost of regularly drinking cranberry juice, as well as the extra calories.
As for cranberry supplements, two studies suggested they may work, but there were obstacles to recommending them.
Jepson said cranberry supplements came in a range of different strengths and the optimal dose and duration of use was unclear. In addition, she pointed out, it was not known whether supplements were equivalent to cranberry juice in the fruit's biologically active substances.
- REUTERS