Effects of voluntary memberships and volunteering on alcohol and tobacco use across the life course: Findings from the German Socio-Economic Panel.

<bold>Background: </bold>It is unclear whether specific components of individual social capital promote or protect against substance use and whether such effects vary across the life course. In this study, we investigated the effects of voluntary memberships and volunteering on alcohol and tobacco consumption in age comparison.<bold>Methods: </bold>Preregistration is accessible at https://osf.io/qhkrn/. We used data from the German Socio-Economic Panel (1984-2015), where alcohol consumption was assessed in 2006, 2008, and 2010 and smoking was assessed at least biennially since 1998. We divided participants into three age groups (14-29, 40-50, and 65-75 years of age at baseline). To disentangle intraindividual change over time and interindividual differences (potential selection effects), we employed multilevel analysis.<bold>Results: </bold>At the within level, voluntary memberships at one occasion predicted higher alcohol consumption a year later in middle-aged and older adults, but memberships had no significant longitudinal effects on smoking. Several positive effects of volunteering on alcohol and tobacco use one year later were found in males. No significant differences in the longitudinal effects between age groups or between nonpolitical and political volunteering emerged. At the between level, voluntary memberships and volunteering were usually associated with more alcohol consumption at low and moderate levels but with less smoking.<bold>Discussion: </bold>Over time, voluntary memberships and volunteering in Germany appear to promote, rather than to protect against, alcohol and tobacco use. On average, more engaged individuals drink more (at moderate levels) and smoke less, which may be due to selection effects. [ABSTRACT FROM AUTHOR]