No meta-analytical effect of economic inequality on well-being or mental health.

Abstract

Exposure to economic inequality is widely thought to erode subjective well-being and mental health^1-5, which carries important societal implications^6-10. However, existing studies face reproducibility issues^11-13, and theory suggests that inequality only affects individuals in disadvantaged contexts^14-16. Here we present a meta-analysis of 168 studies using multilevel data (11,389,871 participants from 38,335 geographical units) identified across 10 bibliographical databases (2000-2022). Contrary to popular narratives, random-effects models showed that individuals in more unequal areas do not report lower subjective well-being (standardized odds ratio (OR_+0.05) = 0.979, 95% confidence interval = 0.951-1.008). Moreover, although inequality initially seemed to undermine mental health, the publication-bias-corrected association was null (OR_+0.05 = 1.019; 0.990-1.049)¹⁷. Meta-analytical effects were smaller than the smallest effect of interest, and specification curve analyses confirmed these results across ≈95% of 768 alternative models¹⁸. When assessing study quality and certainty of evidence using ROBINS-E and GRADE criteria, ROBINS-E rated 80% of studies at high risk of bias, and GRADE assigned greater certainty to the null effects than to the negative effects. Meta-regressions revealed that the adverse association between inequality and mental health was confined to low-income samples. Moreover, machine-learning analyses¹⁹ indicated that the association with well-being was negative in high-inflation contexts but positive in low-inflation contexts. These moderation effects were replicated using Gallup World Poll data (up to 2 million participants). These findings challenge the view that economic inequality universally harms psychological health and can inform public health policy.