A Naturalistic Test of Minority Stress Theory: Examining Social and Psychological Well-Being Trends Across Heterosexual and Sexual Minority Adults from 2009 to 2022

Minority stress theory suggests that shifts toward egalitarianism should reduce well-being disparities between heterosexual people and lesbian, gay, bisexual, and other sexual minorities (LGB+ people). However, few studies have examined well-being trends in these groups over periods of social change. We addressed this issue directly using a large nationwide random sample of New Zealand adults over thirteen years (from 2009 to 2022; <i>N</i>_total = 72,790; LGB+ <i>n</i> = 7,677). In doing so, we tracked people's well-being both before and in the years following major legal changes that increased LGB+ rights. Multigroup latent growth curve models revealed stable well-being differences between LGB+ and heterosexual participants across five domains of well-being, with little evidence of disparities reducing over time. Differences were most pronounced between younger LGB+ and heterosexual groups, with young LGB+ women and men reporting the lowest psychological and social well-being, respectively. These results highlight the need to further examine the impact of minority stress, as well as intersectional identities, on well-being among LGB+ populations.