Food labels often list ingredients like carrageenan, modified food starch, and butylated hydroxytoluene. On this week’s Please Explain we’ll find out what they are, what they do, and why they’re in packaged foods. Michael Jacobson, microbiologist at the Center for Science in the Public Interest a nonprofit health advocacy group that focuses on nutrition and food safety policies, and Marion Nestle, professor in the Department of Nutrition, Food Studies, and Public Health and Professor of Sociology at New York University, explain. Michael Jacobson is the author of Six Arguments for a Greener Diet. Marion Nestle is the author, most recently, of Safe Food: The Politics of Food Safety, Updated and Expanded and Pet Food Politics: The Chihuahua in the Coal Mine.