Frequency of social media use and exposure to tobacco or nicotine-related content in association with E-cigarette use among youth: A cross-sectional and longitudinal survey analysis.

Exposure to social media and its content featuring tobacco products is associated with e-cigarette use among adolescents. This study measured the association between frequency of Instagram, TikTok and YouTube use and exposure to tobacco-related content on each of these platforms with e-cigarette ever-use, current (past 30-day) use and initiation among adolescents. A cross-sectional and longitudinal analyses were used based on a self-reported survey conducted online in January - May 2021-2022 among socioeconomically- and racially-diverse Los Angeles, California high school students (N = 2,036). Adolescents had higher odds of e-cigarette ever-use (adjusted odds ratio [AOR] = 2.16; CI: 1.20;3.90) and current (past 30-day) use (AOR = 3.11; CI: 1.64;5.89) if they used TikTok several times per day, compared to adolescents who used TikTok less frequently or not at all. Adolescents also had higher odds of e-cigarette initiation (AOR = 2.97; CI: 1.53;5.77) if they used TikTok daily or several times per day, compared to adolescents who used TikTok less frequently or not at all. Adolescents had higher odds of e-cigarette ever-use (AOR = 2.60; CI: 2.02;3.35) and current use (AOR = 3.11; CI: 1.64;5.89) if they reported seeing tobacco or nicotine posts, including e-cigarettes, on TikTok at least weekly. Frequent use of and frequent exposure to tobacco content on TikTok is associated with increased risk of e-cigarette use and initiation among adolescents. Tobacco-related content on social media popular among youth, especially on TikTok, requires stronger regulation and better enforcement by platforms of their policies restricting tobacco content.