Cranberries are fruit that can be consumed whole or made into food products such as jellies and juices.
(See also Overview of Dietary Supplements.)
People most often take cranberries to help prevent and relieve the symptoms of urinary tract infections (UTIs). The effectiveness of cranberries in preventing urinary tract infections has been documented in some studies, but not in others. However, recent analyses showed 26 to 33% decreases in UTIs. Natural unprocessed cranberry juice contains anthocyanidins, which prevent Escherichia coli (the bacteria that usually cause urinary tract infections) from attaching to the urinary tract wall.
Some people take cranberry juice to reduce fever and treat certain cancers. However, there is no scientific proof that it is effective for these uses.
The following is an English-language resource that may be useful. Please note that THE MANUAL is not responsible for the content of this resource.
National Institutes of Health (NIH), National Center for Complementary and Integrative Health: General information on the use of cranberry as a dietary supplement