PROJECT SUMMARY While digital marketing of tobacco products is becoming increasingly common, the role of social media platforms in tobacco control is still understudied. An emerging body of research shows that social media promotion of flavored tobacco products (i.e., electronic nicotine delivery systems (ENDS), cigars, cigarillos, little cigars, hookah/waterpipe, pipe, smokeless tobacco, heat-not-burn products) is rapidly growing. These messages are currently under-regulated, target youth, often contain misinformation, and feature branded merchandise and celebrity or “influencer” promotion. Youth use social media at higher rates than the general population in the U.S., which potentially multiplies the effect of targeted social media marketing. The existing regulatory imbalances in treatment of flavored tobacco products (FTPs) and digital marketing of tobacco products may explain recent trends in youth FTP use. In particular, the recent exponential rise in social media advertising coincided with significant increases in ENDS and other FTP use among U.S. youth, which has erased recent progress in reducing overall tobacco product use among youth. Understanding the impact of exposure to social media content can inform tobacco regulatory science. Unfortunately, to date, no studies have examined the impact of social media marketing of such FTPs. This project will fill this critical research gap. The overarching goal of this project is to examine the effects of exposure to FTP-related social media content and provide timely scientific basis for regulatory actions on restricting marketing of these products. The specific aims of the proposed project are Aim 1: to identify and characterize potentially regulatable social media message content related to FTPs by source (e.g., brand, influencer/community, regular consumer) and major themes (e.g., new-user targeting, health risks, flavor-type); Aim 2: to examine the impact of exposure to commercial and influencer FTP content on product sales and on youth and young adult awareness, risk perceptions, intentions to use, initiation, and patterns of use of FTP products; and Aim 3: to study whether/to what extent FTP regulatory policies modify the impact of exposure to social media content on FTP product sales and youth and young adult awareness, risk perceptions, intentions to use, initiation, and patterns of use of FTP products. These aims will be accomplished by applying classic theories of health behavior and advertising, along with innovative analytic methods, to a unique combination of data sets, including social media data from Twitter and Instagram, individual-level data on exposure to tobacco marketing, tobacco attitudes, and tobacco use from the Population Assessment of Tobacco and Health (PATH) surveys, FTP sales volume data from Nielsen store scanner data, and state/local FTP policy data collected by NORC. The findings from this project will (a) inform regulatory science by highlighting potential regul...