Scientists are building a better sweet potato to fight blindness.

Vitamin A deficiency is the leading cause of preventable blindness in children. It also increases the risk of death from severe infections. About 250 million preschool children across the world are vitamin A deficient. Many of these live in Africa and South-Eastern Asia.
Fortunately, vitamin deficiency is preventable. In the United States, vitamin-fortified foods, like milk and cereals, are widely accepted. Another method, bio-fortification, is a crop-based option. This is the process of developing nutrient-rich varieties using molecular techniques or conventional breeding. The result is produce that provides better nutrition, right from the field.
Bio-fortification of sweet potatoes is a promising method to combat vitamin A deficiency in South Africa. The orange-fleshed vegetable already contains high levels of beta-carotene, which our bodies convert to vitamin A. Sweet potatoes are also a staple in the South African diet.
“Sweet potato is very popular in Africa,” says Sunette Laurie, a senior researcher with the Agricultural Research Council in Pretoria, South Africa. In South Africa, sweet potatoes are a traditional crop for rural families. “We realized it would be great if we could develop a local variety [of sweet potato] which has good yield, high dry mass, and desirable taste attributes, and promote it to combat vitamin A deficiency,” says Laurie.