A native of the Japanese island Okinawa, the Okinawa Sweet Potato with its light brown skin and unusual purple flesh is richly nutritious and surprisingly sweet.

They are wonderfully versatile and they can be a key ingredient in everything from chips to ice cream. They have a naturally creamy flavor and texture and hold their shape well for salads.

The designer sweet potato, grown for its anti-cancer purple pigment, is also said to contain anti-ageing and antioxidant chemicals. An expert in the US has developed the variety of sweet potato with a thick purple skin and flesh to increase its cancer-fighting properties. Coloring contained the chemical anthocyanin, which lowers the risk of cancer and could even slow down certain types of the disease. "The color is the important part because the purple color is responsible for the amount of anthocyanin in the potato".