Is cranberry juice really good for uti or cystitis?

Cystitis/ UTI: Cystitis is part of the UTI family and cranberry juice has been shown to prevent the adhesion of bacteria to bladder membranes and doing so decreases the urine infection rate.

Unlikely: Only one study has shown cranberry juice to be helpful (elderly women with chronic catheters). My advice to my patients is "if you like it, drink it;if you don't, drink h2o".

As a preventative: Cranberry juice does not cure utis or cystitis. Is a fairly good preventative because it contains a chemical which makes it much more difficult for bacteria to adhere to the bladder lining and thus cause a uti.