Dr. Joshua Petimar is a postdoctoral research fellow at the Harvard T.H. Chan School of Public Health. He works primarily with Dr. Jason Block to examine nutrition policies (such as the federal calorie labeling law) that aim to improve dietary choices and reduce obesity on a population level. His current projects use point of sale data from fast food restaurants and supermarkets to generate evidence on the effectiveness of these policies. He additionally works with Dr. Emily Oken to investigate the environmental and biological determinants of obesity in children and adolescents within the Project Viva epidemiologic cohort. He received his doctorate in Nutrition and Epidemiology from Harvard, where he studied the relationships between diet, obesity, and cancer using methods developed for causal inference.