"Blueberry is a plant. People use the fruit and leaves to make medicine. Be careful not to confuse blueberry with bilberry. Outside of the United States, the name ""blueberry"" may be used for a plant called ""bilberry"" in the U.S. Blueberry is used for a variety of conditions including improved memory and thinking skills, prevention of cancer and heart disease, and treatment of urinary tract infections (UTIs) and depression. But there is limited scientific research to support any of these uses."