Sugar has the same problem as a lot of other commodities: oversupply from key producers and a lack of global demand.
Every glut has its wrinkles, of course. Oil has the OPEC states facing off against US shale producers; cotton has China facing off against… everybody. For sugar, a drought last year in Brazil, a major sugar producer, isn’t doing as much as you’d think to boost prices, because European demand is down and the Brazilian real is too weak.
This week, rains in Brazil over the last few months had analysts raising their near-term crop yield estimates, which means that sugar’s bitter year might stay that way for a while.