It’s become a nearly standard claim that economics inequality makes people feel worse-off, or perhaps even leads to mental illness. However, Nicolas Sommet, Adrien A. Fillon, Ocyna Rudmann, Alfredo Rossi Saldanha Cunha and Annahita Ehsan did what is called a “meta-analysis” of the available studies–that is, they went back and looked at the underlying data, methods, and findings of the available studies. They state their findings bluntly in the title: “No meta-analytical effect of economic inequality on well-being or mental health” (Nature, published November 26, 2025, a readable overview/summary of the study is available here, and I quote from it below).
It’s perhaps useful to clarify the question being asked. Many studies have used survey data that asks people questions about themselves, and also asks them to rank their own well-being–say, on a scale from 1-7. Those with lower incomes will generally report lower well-being than those with higher incomes. But that finding shows only that income is associated with lower well-being–not that the degree of inequality affects the level of well-being.
Instead, imagine that you are in a society where inequality rises over time. Does the reported well-being of those at the lower end decline as inequality rises? Or imagine that you are comparing between people in different societies, some with greater inequality than others. Do those with lower income levels who also live in higher-inequality societies consistently report a lower level of well-being, compared with those with lower income levels who live in lower-inequality societies? Here’s a summary of the method and results of the study:
[E]xisting studies have mostly looked at a small number of countries, regions or cities, making their results sensitive to random variations and hard to replicate. Researchers have tried to address this limitation with meta-analyses (methods that combine findings across studies), but earlier efforts included only 9–24 studies and rarely examined for whom and when inequality might affect well-being and mental health.
To review the relationship between economic inequality and well-being or mental health, we screened thousands of scientific papers and contacted hundreds of researchers to identify all work on the subject. We included 168 studies, involving a total of more than 11 million participants. Nearly all samples were nationally representative, spanning countries across most world regions. We extracted more than 100 study features from each paper and linked them to more than 500 World Bank indicators to describe each study’s national context. We summarized the papers’ findings and conducted further analyses, including replicating results using data from the Gallup World Poll, which from 2005 to 2021 surveyed more than two million respondents from more than 150 countries.
First, we found that people living in more-unequal places did not, on average, report lower well-being (life satisfaction or happiness) than those in less-unequal places. The average effect across studies was not statistically significant, was practically equivalent to zero and did not depend on study quality, design, outcome or geographic scale. Second, although some studies reported that people in more-unequal places had poorer mental health, we found that this pattern reflected publication bias: small, noisy studies that reported larger effects were over-represented .. After adjusting for this bias, the average association between economic inequality and mental health shrank to essentially zero.
Further analyses showed that the near-zero averages conceal more-complex patterns. Greater income inequality was associated with lower well-being in high-inflation contexts and, surprisingly, higher well-being in low-inflation contexts. Greater inequality was also associated with poorer mental health in studies in which the average income was lower. We conclude that inequality is a catalyst that amplifies other determinants of well-being and mental health (such as inflation and poverty) but on its own is not a root cause of negative effects on well-being and mental health.
Of course, no single study or meta-study will offer a final consensus resolution to a big question like this one. Moreover, the statement that living in a society with greater income inequality does not make the poor worse off does not contradict the statement that being poor–regardless of the level of inequality in your society–can have negative effects on subjective well-being and on mental health.
Hat tip: I ran across this study because of a mention at the ever-useful Marginal Revolution website.
