SYSTEMATIC REVIEW article
Front. Med.
Sec. Hepatobiliary Diseases
Volume 12 - 2025 | doi: 10.3389/fmed.2025.1670932
The relationship between tobacco and non-alcoholic fatty liver disease incidence: a systematic review and meta-analysis of observational studies
Provisionally accepted
- Affiliated Jinhua Hospital, Zhejiang University School of Medicine, Jinhua, China
Select one of your emails
You have multiple emails registered with Frontiers:
Notify me on publication
Please enter your email address:
If you already have an account, please login
You don't have a Frontiers account ? You can register here
Background This meta-analysis investigates the relationship between smoking and non-alcoholic fatty liver disease (NAFLD) risk. Methods Observational studies (cohort, case-control, cross-sectional) were systematically searched in PubMed, Web of Science, EBSCO, and Cochrane Library up to December 2024. Adjusted odds ratio (OR) and corresponding 95% confidence interval (95% CI) were used to assess the association. Results A total of 19 studies, composing 450,130 participants were included. Active smoking significantly increased NAFLD risk (OR = 1.30, 95% CI: 1.21–1.40, p < 0.001), with stronger effects observed in current smokers (OR = 1.41, 95% CI: 1.22–1.63, p < 0.001). A dose-response relationship was evident: ≥20 pack-years of smoking elevated risk by 32% (OR = 1.32, 95% CI: 1.18–1.49, p < 0.001). Subgroup analyses revealed amplified risks in metabolically compromised individuals, including those with BMI ≥24 (OR = 1.43, p < 0.001), TG ≥1.2 mmol/L (OR = 1.41, p = 0.003), and SBP ≥125 mmHg (OR = 1.65, p < 0.001). Passive smoking showed a marginal association (OR = 1.13, 95% CI: 1.09–1.16, p < 0.001). Conclusion Smoking is an independent risk factor for NAFLD, particularly in individuals with metabolic dysregulation. Public health strategies targeting smoking cessation and metabolic control may mitigate NAFLD burden.
Keywords: NAFLD, Active smoking, passive smoking, Incidence, Meta-analysis
Received: 22 Jul 2025; Accepted: 22 Sep 2025.
Copyright: © 2025 Jin, Zhang and Huang. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: Yiping Huang, jhhuangyp@163.com
Disclaimer: All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher.