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Published on: August 6, 2013
Smoking depictions in the manga 'ONE PIECE' over its 27-year serialisation: a segmented time series analysis of Sanji
Hiroko Tobari1,2, Chiharu Shimizu3, Shiori Kawamura3
1School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo, Japan h-tobari@umin.ac.jp.
Objectives:
This study investigates smoking depictions in the globally popular manga ONE PIECE over its 27-year publication period and its associations with tobacco control measures implemented in Japan.
Design:
Time-series study.
Setting:
Volumes 1-110 (1121 episodes) of ONE PIECE published between August 1997 and December 2024.
Interventions:
Smoking scenes were identified and quantified by panel-based content analysis.
Main Outcome Measures:
Prevalence of smoking panels relative to the total number of panels per volume.
Results:
The overall prevalence of smoking panels was 4.7%, with a significant downward trend (p<0.001). Smoking depictions of Sanji, the only smoker among the 10 core characters in the series, accounted for 54% of the total of 5076, and his smoking portrayal significantly declined over the 27-year publication period (p=0.007). Interrupted time series analyses demonstrated statistically significant slope changes indicating decreasing trends in Sanji's smoking depictions following the implementation of the revised Health Promotion Act (p<0.001).
Conclusions:
Despite this decline, smoking behaviour and tobacco product depictions continued to appear in the series. Policies with adolescent-focused, legally binding implications for smoking environments were associated with reductions in the smoking depictions of a core character. Given the global reach of Japanese manga among young audiences, strengthening regulations on smoking depictions and enhancing media literacy education for adolescents may be necessary to reduce the risk of smoking initiation.
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