Blueberries are nutritional stars bursting with flavour while being very low in calories. Blueberries are the fruits of a shrub that belongs to the heather family, whose other members include the cranberry and bilberry. Blueberries are about the size of a pea and dark in color, ranging from blue to maroon to purple-black, and feature a white-gray waxy bloom that covers the berry's surface and serves as a protective coat. The skin surrounds a translucent flesh that encases tiny seeds.