Copromotion across commercial determinants of health: content analysis of smokeless tobacco social media messages referencing alcohol, 2016-2021.

Objective: The goal of this study is to analyse the amount and content of alcohol-themed smokeless tobacco (ATST) messages on social media, characterise major themes and identify key sources of these messages. These insights are crucial for understanding the tobacco and alcohol industries' marketing strategies and informing effective tobacco control policies.

Methods: We analysed 777 336 smokeless tobacco-relevant tweets from August 2016 to October 2021 and identified 36 804 (4.7%) ATST tweets. Three types of accounts that generated ATST tweets were detected using machine learning techniques: commercial, bot and regular users. The content analysis categorised major themes and examined language patterns of ATST messages posted by the most active accounts.

Results: ATST content was dominated by culture/lifestyle themes (71.8%) (eg, rural/country culture), followed by couse patterns (14.0%) and alcohol flavour references (4.3%). Commercial accounts contributed 4.9% of ATST tweets, and top commercial accounts showed patterns of coordinated posting activity, with identical promotional content for smokeless tobacco accessories and alcohol-themed hashtags featured across accounts. Bot accounts contributed 4% of ATST content. Commercial and bot account reach exceeded regular user account followership.

Conclusion: Our analysis of ATST content on X/Twitter revealed the evidence of strategic comarketing of smokeless and alcohol products, specifically coordinated activities leveraging cultural narratives to normalise substance use. Social media's unregulated space facilitates cross-substance promotion, linking smokeless tobacco with alcohol through strategic product placement and lifestyle associations. These findings highlight the need for new prevention and regulatory approaches to address cross-substance marketing, including social media-specific policies to restrict coordinated promotion of harmful products.