Lucie Nahimana, a mother of four in Burundi, breaks up moldy cassava to be milled into black flour at the local mill. According to relief workers, black flour has little nutritional value, but more and more people are buying it because of the increase in food prices in countries such as Burundi. Black flour is the cheapest on the market, but has still doubled in price since the start of the year. (Evelyn Hockstein/Evelyn Hockstein / MCT)