When it comes to treatment rather than prevention, another Cochrane review has searched for relevant studies, but found that there is not yet enough evidence to come to any firm conclusions. What about the women who swear it works for them? The problem is that without a controlled trial they can’t know whether their infection would have got better on its own, or when and if they would have the next bout of cystitis.
So the only guaranteed treatment for urinary tract infections is antibiotics. With the risk of increased antibiotic resistance, an alternative treatment for such everyday infections would be welcome. But for the moment, it’s impossible to say whether cranberry juice is it.
You can hear more Medical Myths on Health Check on the BBC World Service.
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