You\u2019ve probably heard it before: cranberry juice can prevent urinary tract infections (UTIs). But is it true?\nMichelle Jo Semins, MD, assistant professor, Department of Urology, weighs in on this common advice with the facts about the effects of cranberry juice on UTIs.\nMyth or Fact: Cranberry Juice Can Prevent UTIs.\n\u201cThe short answer is: we don\u2019t really know,\u201d Dr. Semins says. \u201cThe long answer is: people have been using cranberry substances (juices, supplements, etc.) to prevent UTIs for decades, but we still do not have enough strong, consistent evidence to say without a doubt that it can be effective.\u201d\nBefore this question can really be answered, Dr. Semins says a proper study has to be done.\n\u201cCurrent studies have small numbers and lack randomization of participants,\u201d she says. \u201cMany have high dropout rates, low compliance with treatment, short trial duration, and are underpowered to detect benefit.\u201d\nCranberry does not lower the pH of your urine enough for the acid excreted to function against bacteria. Although it is not confirmed, the active ingredient that doctors believe prevents UTIs is called proanthocyanidin. It is thought to prevent bacteria from attaching to your bladder wall and causing infection.\n\u201cThere is no consensus on which cranberry products are best, or on optimal dosage or duration that may prevent UTIs,\u201d Dr. Semins says. \u201cWhat is likely most important is how much active ingredient (proanthocyanidin) is present.\u201d\nAlthough the effectiveness is currently unknown, doctors and researchers do know that cranberry is a safe option. Based on current studies, the group with the most potential for benefit is young and middle-aged females with recurrent UTIs.\nA known urinary benefit of drinking cranberry juice is one that is achieved with any fluid \u2013 hydration.\n\u201cStaying well-hydrated is very important for the urinary tract,\u201d Dr. Semins says. \u201cThere is also some literature that suggests cranberry may have an anti-inflammatory property, but this is not well-studied.\u201d\nIt\u2019s important to be aware that cranberry can interact with Coumadin\u00ae (warfarin) and drugs that are metabolized by the liver, so be sure to ask your primary care doctor before starting any new supplements.\nIf you are experiencing recurrent urinary tract infections, talk to your doctor or urologist about prevention and long-term treatment options that may be right for you.