Racial Trauma among Multi-Ethnic Minority Young Adults Affects Nicotine, Alcohol, and Cannabis Use Differently than among Mono-Ethnic Minority Young Adults

Americans who identify as “Two or More Races” are one of the fastest-growing racial/ethnic minority groups. More research is needed on the intricate and core life experiences that influence psychological health and related behaviors of these individuals. In this study, we use a sample of racial/ethnic minority young adults (REMYA) to examine how perceived racial trauma and psychological well-being (PWB) influence substance use, as mediated by mental health variables. We hypothesized that PWB would interact with racial trauma to influence substance use and that these associations would vary by mono- <i>vs.</i> multi-racial/ethnic identity. We combined Healthy Minds Study (HMS) data 2021–2023 for self-identified REMYA (<i>N</i> = 59,529), with 25.3% multi-racial. We conducted moderated mediation path analyses, stratified by mono- <i>vs.</i> multi-ethnicity. Multiple group analysis tested non-invariance. For mono-ethnic REMYA, PWB was associated with lower anxiety and depressive symptoms, count of substances used, but higher likelihood of any use (<i>p</i>’<i>s</i> &lt; 0.001); effects of PWB on any use were augmented by racial trauma, partially mediated <i>via</i> depressive symptoms (<i>p</i> &lt; 0.001) but not anxiety. For multi-ethnic REMYA, PWB was associated with lower anxiety and depressive symptoms (p’s &lt; 0.001), but not substance use, completely mediated <i>via</i> depressive symptoms (<i>p</i> &lt; 0.001). The negative associations between PWB and depressive and anxiety symptoms were dampened by racial trauma. Multiple group analyses confirmed non-invariance. The protective effects of PWB on mental health are dampened by racial trauma for racial minority young adults. For multi-ethnic young adults, depressive symptomatology may be a modifiable factor to mitigate effects of racial trauma.