Investigating psychological distress and peer influence in the longitudinal path linking food insecurity to adolescent substance use: a nationwide low-income cohort study.

Food insecurity (FI), defined as the limited or uncertain availability of nutritionally adequate and safe foods, remains a major life concern among many poor subpopulations. Few investigations have been made into the mechanism underlying its impact on adolescent substance use. This study aimed to examine the longitudinal relationship between FI and cigarette and alcohol use among economically disadvantaged adolescents and then explore the role of psychological distress and peer substance use in the aforementioned association. Data of 1,243 adolescents (Mage = 13.3 years; 645 males) were obtained from a nationwide cohort study on Taiwanese adolescents from low-income families. Multiple hierarchical regression analyses based on generalized linear mixed-effects models with binomial distribution found that FI was consistently associated with cigarette smoking (β = 0.458, p < 0.001) but not alcohol drinking (β = 0.142, p = 0.143) when both psychological distress and peer substance use were adjusted. In the moderated mediation analysis based on bootstrap methods, we observed that psychological distress mediated the association between food insecurity and alcohol drinking (β = 0.036, 95% CI = 0.015-0.063) but not cigarette smoking (β = 0.018, 95% CI =-0.001-0.037). Furthermore, the indirect effects varied by peer drinking status (index of moderated mediation = 0.04, 95% CI 0.015-0.072). Clinical and public health attention should be given to evaluating food-insecure adolescents' psychological well-being and peer influence when counseling their substance use issues.