This purple smoothie is bursting with antioxidants, thanks to the blueberries and frozen pineapple. My kids love the bright purple color, and it also freezes well for popsicles!
Combine the water, orange juice, banana, pineapple, and blueberries in a high-speed blender, and blend until very smooth. Add a splash more water, if needed to help it blend.
Pour into a glass and serve right away.