For more than a century cancer cell metabolism has been viewed as something of a paradox, but newly reported research by scientists at Washington University in St. Louis shows that it might not be such an anomaly. The rate at which tumors consume glucose has been exploited by doctors as a way to diagnose and stage cancer, and has pointed to the possibility that using drugs—or even eating a sugar-free diet—to limit glucose uptake might “starve” cancer cells to death. The newly reported results, which could help to explain the apparently wasteful use of glucose by cancer cells, also raise questions about this strategy.