The Okinawan Sweet Potato

The Okinawan sweet potato was one of the few things that I missed out on when we visited Okinawa. There, purple sweet potatoes are a part of the culture in the cooler months of autumn and winter. Small trucks with ovens on the back go around selling fresh roasted sweet potatoes. I hear they are delicious just as they are. You peel back the skin and bite into the purple, sweet, filling, warm inside.


The sweet potato is highly revered in Okinawa. That’s because it saved many lives there. The history of the Ryukyu Kingdom is full of hardships: over-taxation from China and Japan, drought and major typhoons that often wiped out crops. (Not to mention the more recent devastation from World War II.)

A man called Noguni Sokan is credited with bringing the purple sweet potato to the Ryukyu Kingdom from China in the early 1600’s. He discovered that it grew well in its new homeland. So well that 400 years later we call it the Okinawan sweet potato. The whole plant is edible. It is hearty enough to survive typhoons. It provided nutritious food to combat starvation in the Ryukyu Kingdom.


The Okinawan sweet potato has tan skin hiding a purple interior. When cooked, the inside gets darker. Like many dark fruits and vegetables, it holds superfood status. It contains more antioxidants than blueberries. Plus a whole lot of vitamins and minerals. This article and its resources list out the nutritional benefits of this prized tuber.


History says that this sweet potato started with the Aztecs in South America. They traded this healthy tuber to Europeans. Then Spaniards brought it to the Philippines. Then, traders took it to China. That is where the journey of the Okinawan sweet potato is much like that of Okinawan karate.


Like the sweet potato, martial arts didn’t originate in China, but during their early development they traveled there. From China, both the sweet potato and a formal martial arts system traveled to the ancient Okinawa (then called the Ryukyu Kingdom). For hundreds of years, the martial arts were developed into a working system for people on the island. As well, the potato crops were developed into a food that the people used and respected.

Later, mainland Japan recognized the value of the Okinawan martial arts. Similarly, they had needed and valued the sweet potato when they went through hardships. Both karate and the Okinawan sweet potato gained popularity in mainland Japan. From there they branched out to benefit the rest of the world.

ENJOY THE OKINAWAN SWEET POTATO purple and Okinawan sweet potatoes

There are many varieties of purple sweet potatoes, as seen here. In my experience, the best place to find them is the produce section of an Asian market. This is the time of year to look. They are not there year-round in our local Asian markets. When you do get some, roast them and to get the experience of Okinawa, try them plain. Some people like a little salt or butter added. Enjoy, to your health!

-Jenifer Tull-Gauger

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