Battle of the Cranberries: How Do They Work to Prevent Bladder Infections

Cranberries remain one of the most commonly used natural medicines for bladder infections (UTIs). But findings have been conflicting over the years, and people might be confused about which cranberry products they should try. Here’s the latest update.

Taking cranberry by mouth seems to help reduce the risk of recurrent and first-time UTIs in adult females by 26-33%. Theories about how cranberry works have been inconsistent. People used to think that it worked by acidifying the urine and therefore slowing the growth of bacteria, but that’s not the case. Instead, it seems that chemicals in cranberry, called proanthocyanidins (PACs), keep bacteria like E. coli from sticking to cells that line the urinary tract. 

People ask which cranberry product they should try, and unfortunately, there isn’t a clear answer. There’s no strong evidence for any one specific product. A recent study shows that the PACs in extracts from cranberry JUICE might work better than extracts from whole cranberry FRUIT. But more research is needed in this area to confirm.

Until we can get more research, the best bet is to use cranberry juice or cranberry juice extracts for UTI prevention rather than whole fruit products. Regardless of what formulation is used, cranberry products seem to be safe for most people. 

Lastly, it is clear that there’s no evidence that cranberry juice or cranberry supplements can TREAT UTIs – patients should always seek out care from their healthcare provider for an existing UTI.