Taking a cranberry supplement probably won’t help your urinary tract infection. While cranberry products aren’t necessary ineffective, not all products are created equal. “Tests of seven popular cranberry-pill brands in the U.S. showed that most contained too little of the key bacteria-fighting ingredient to have any effect… More recent investigations show that cranberries or cranberry juice may actually work because they contain proanthocyanidins — antioxidant “flavonoids” like those found in blueberries, grape seeds and chocolate that also prevent bacteria from sticking to the bladder wall and beginning the growth process…cranberry products need to contain at least 36 milligrams of proanthocyanidins per gram.” Researchers concluded that natural cranberry foods were the best choices to prevent infection.