So when the Cochrane review says. Cranberries (usually as cranberry juice) have been used to try and prevent urinary tract infections (UTIs). Cranberries contain a substance that can prevent bacteria from sticking on the walls of the bladder. This may help prevent bladder and other urinary tract infections.This review identified 10 studies (1049 participants) comparing cranberry products with placebo, juice or water.There was some evidence to show that cranberries (juice and capsules) can prevent recurrent infections in women.his may help prevent bladder and other urinary tract infections. This review identified 10 studies (1049 participants) comparing cranberry products with placebo, juice or water. There was some evidence to show that cranberries (juice and capsules) can prevent recurrent infections in women.