Preregistered Meta-Analysis on Weight Stigma is Top Downloaded Article in Obesity Reviews

A preregistered meta-analysis on the association between weight stigma and mental health which appeared in the journal Obesity Reviews is one of the top downloaded in the publisher’s recent history. ZPID director Michael Bosnjak is one of the co-authors.

Christine Emmer (Mannheim University), Michael Bosnjak (ZPID), and Jutta Mata (Mannheim University) have studied the association between weight stigma and mental health.

"There has been considerable research on the relation between weight stigma and mental health, but no quantitative synthesis of the empirical evidence is available to date", says Jutta Mata. "This meta‐analysis fills this gap. Age, gender, and factors presumed to exert a protective role were tested as potential moderators."

While the association between weight stigma and mental health was corroborated as expected, surprisingly, all theoretically presumed moderator hypotheses had to be rejected. Body weight was a significant moderator, indicating a stronger association between weight stigma and diminished mental health with increasing body mass index. Future research might focus on explaining the heterogeneity of findings and on testing causality as well as potential underlying mechanisms.

 "We are pleased that the meta-analysis is so well received, as this emphasizes the relevance of weight stigma as a societal issue", says Christine Emmer, first author of the study. "One-third of the world's population is affected by overweight or obesity. The strong association between weight stigma and mental health suggests that addressing weight stigma is a promising avenue to protect their psychological well-being. Education about overweight and weight stigma as well as policies to protect against stigma is an important challenge for better mental health on a global level."

"Preregistered meta-analyses in general, and this synthesis specifically, typically yield surprising and trustworthy findings decisively shaping theory development and public policy measures", says ZPID director Professor Bosnjak. 

Meta-analyses are a concern for ZPID. The research unit "Research synthesis methods in psychology" even focusses on it aiming to contribute to the recent discussion on replicability, transparency, and research integrity in psychology, among others.

The article "The association between weight stigma and mental health: A meta‐analysis" is available open access: https://doi.org/10.1111/obr.12935. The study was preregistered.