How consumer worries are driving menu makeovers

For years, Americans have heard warnings and and expressed worries about what’s in their food, from artificial ingredients to antibiotics. Increasingly, the food industry is taking notice and making changes. What do consumers need to keep in mind about a flurry of recent announcements? Gwen Ifill talks to Michael Moss, author of "Sugar, Salt, Fat," and Allison Aubrey of NPR.