Christina A. Roberto, PhD, is an Assistant Professor of Social & Behavioral Sciences and Nutrition at the Harvard T.H. Chan School of Public Health. She is a psychologist and epidemiologist whose research aims to identify, understand, and alter the environmental and social forces that promote unhealthy eating behaviors linked to obesity and eating disorders. In her work, she draws upon the fields of psychology, behavioral economics, marketing, and public health to answer research questions that can provide policymakers and institutions with science-based guidance. Ichiro Kawachi, MD, PhD, is the John L. Loeb and Frances Lehman Loeb Professor of Social Epidemiology and Chair of the Department of Social & Behavioral Sciences at Harvard T.H. Chan School of Public Health, where he has taught since 1992. He has previously coedited Social Epidemiology, Neighborhoods and Health, Globalization and Health, and the Oxford Handbook of Public Health Practice, all published by Oxford University Press. Kawachi lectures about social epidemiology through the Harvard University Massive Open Online Course (MOOC) platform, edX. His course, Health and Society (PHx 201), is a version of the class that he has taught for twenty years at Harvard. In 2013-1014, 35,000 students from all over the world were enrolled in the MOOC course.