Nkosi, LungileAyo-Yusuf, Olalekan Abdulwahab2026-03-312026-03-312026-02Nkosi, L., Ayo-Yusuf, O.O. Clustering of lifestyle risk behaviours and food insecurity in a population of South African adults: a cross-sectional study. Discover Public Health 23, 209: 1-17 (2026). https://doi.org/10.1186/s12982-026-01536-7.3005-0774 (online)10.1186/s12982-026-01536-7http://hdl.handle.net/2263/109350DATA AVAILABILITY : The data supporting the findings of this study are available from the Principal investigator, Prof. Olalekan Ayo-Yusuf, upon reasonable request (Email: Lekan.Ayo-Yusuf@up.ac.za).BACKGROUND : Unhealthy lifestyle behaviours may be associated with food insecurity, yet limited research in low- and middle-income countries has examined the clustering of such behaviours and their association with food access challenges. This study explores the clustering of lifestyle risk behaviours, including polytobacco use, and their association with food insecurity among South African adults. METHODS : Data were drawn from the 2021 Tobacco and Other Modifiable Risk Behaviours Online Survey, comprising 11,093 adults aged 18 years or older. Weighted logistic regression models were used to examine associations between lifestyle risk behaviours (any or poly tobacco/nicotine product use, heavy drinking, unhealthy diet, physical inactivity, inadequate sleep) and food insecurity. Statistical significance was set at p < 0.05. RESULTS : Overall, 84.1% (95% CI: 72.90–96.65) were found to engage in two or more risk behaviours, while 7.0% (95% CI: 5.29–9.30) reported all five. The most common clustering involved physical inactivity and inadequate sleep (10.8%; 95% CI: 8.17–14.10). Concurrent daily polytobacco use and heavy drinking were significantly associated with food insecurity (OR = 2.20; 95% CI: 1.10–4.40). Severe financial difficulty (OR = 9.30; 95% CI: 4.78–18.11), Black African race (OR = 8.94; 95% CI: 6.44–12.43), unemployment and lower education were also associated with increased odds. CONCLUSION : Addressing financial hardship, racial disparities, and co-occurring lifestyle risk behaviours is critical to mitigating food insecurity and reducing non-communicable disease risk in South Africa.en© The Author(s) 2026. Open Access. This article is licensed under a Creative Commons Attribution 4.0 International License.ClusteringFood insecurityNon-communicable diseases (NCDs)PolytobaccoRisk behaviourArticle