Is sugar toxic? A 90 minute YouTube video of pediatrics professor Robert Lustig trying to answer the question has counted 800,000 hits. The New York Times has an interesting piece in the magazine section that explains why sugar is on the minds of so many Americans. Marion Nestle is a professor of nutrition at New York University and the author of "What to Eat" and Barry Popkin is the distinguished professor of global nutrition at the University of North Carolina school of public health. Together they explain why sugar is a major public health risk, and what we should do to control it.