It's delicious. It's nutritious. But in sub-Saharan Africa, the orange-fleshed sweet potato has an image problem.
Unlike white- and yellow-fleshed varieties commonly found in Africa, orange sweet potatoes are loaded with vitamin A.
These vitamin-packed root vegetables could help fight vitamin A deficiency in the developing world. According to the World Health Organization, vitamin A deficiency leads to death from serious illness for as many as 250,000 children each year. Twice that many develop night blindness, another common result of vitamin A deficiency.
A little sweet potato could go a long way to solving that problem.
"One root a day would get you set for vitamin A," says Jan Low. She is leading a project at the International Potato Center, a major global research center, to increase consumption in sub-Saharan Africa, where vitamin A deficiency is a major public health problem.
'Crop of the poor'
But, Low adds, "We do have an image problem with the sweet potato. It's seen as a crop of the poor."
Low says sweet potatoes are mainly grown by poor women because they can rely on the vegetable to feed their families if the maize crop fails.
To make orange sweet potatoes acceptable to a wider audience, she says, you have to make people want it. And that means advertising and marketing.
"Look at Coca-Cola," Low says. "There's a product that's managed to spread to the remotest corners of the world through marketing. Why aren't we doing that with good food crops?"
A market vendor in Uganda promotes vitamin A-rich orange sweet potatoes.
Low worked on a research project in four districts in Mozambique and three in Uganda that took to the streets, markets and airwaves to relay information about the nutritional benefits of the orange-fleshed sweet potato.
Radio ads touted the tuber's power to "fight diseases, make you strong, clear your skin and make you look healthy."
In remote areas where radio does not reach, they spread the sweet potato message through community-theater performances - complete with singing, dancing and storytelling.
And everywhere they went, promoters wore orange t-shirts and hats. They painted billboards and market stalls orange. They drove orange vehicles. At a recent conference in Washington, DC, Jan Low could be seen walking the halls in an orange dress.
"Orange color actually proved to be an effective tool for building an orange brand to promote the sweet potato and become associated with good health," she says.
They even came up with slogans to include in all their marketing efforts. In Mozambique they used the phrase, "O doce que dá saúde," which, in Portuguese, means, "the sweet that gives health."
Low has not yet published research on what impact they are having. But she sees indications that the message is getting through.
She says, "The traders in the markets cut a little bit off the end of the sweet potato and they make a little round piece of it and they stick it on top [of their merchandise]. And as you're walking by they say, 'This is the vitamin-rich one! This is the vitamin-rich one!'"
Dan Gustafson, head of the Washington, DC, office of the U.N. Food and Agriculture Organization, is optimistic about the effort to bring the orange-fleshed sweet potato to sub-Saharan Africa. He says the history books are littered with well-intentioned efforts to introduce crops that produce more, or resist diseases or have some other benefit.
"Most of those have ended in failure," he says, because they did not take into account what consumers wanted.
But the difference between orange sweet potatoes and the sweet potatoes African consumers already eat is not that big, he says.
"Because you've got advertising, and you've got a difference that isn't radical, I think it will work," Gustafson adds.
With the help of an image make-over, Gustafson says the orange-fleshed sweet potato can play a substantial part in reducing malnutrition in some of the world's poorest places.