Protective factors may modify an individual’s response to stressors. Correspondingly, the connection between heavy alcohol use and mental health may vary by protective factors. Social support has been shown to be connected to good mental health and it has also been postulated to have stress-buffering effects12. Another potential buffering factor could be socioeconomic status. It has been found to be systematically associated with health13–14 and severe mental disorders,15–16 but not as systematically with common mental disorders.17 For severe alcohol-related outcomes, a given
level of alcohol consumption has been reported to be associated with a higher risk among manual than among non-manual workers.18 Whether such effect modification exists for the effect of alcohol use on mental health is not known.