Lack of diversity an obstacle to mental health data, say UCC researchers

A new study led by researchers at UCC has found that one of the biggest obstacles facing mental health research is not a lack of technology or data, but a lack of global diversity in the people being studied.

Published in Nature Mental Health and led by Chilean medic Dr Benjamin Valderrama and neuroscientist Professor John F Cryan, the paper argues that studies on the mental health area have become overwhelmingly concentrated on wealthy, industrialised nations and therefore limiting scientific discovery.

The authors argue that expanding microbiome gut brain research across Latin America, Africa, Asia and other underrepresented regions is not only an issue of equity, it is crucial if scientists are to uncover universal biological principles which can improve mental health worldwide.

One of the central ideas of the publication is that many countries in the global south provide unique opportunities to understand how environment shapes mental health.

Rapid urbanisation, changing food systems, environmental transitions and socioeconomic gradients often exist within relatively small geographical regions, creating what the authors describe as “natural experiments” that cannot easily be reproduced in laboratories.

Dr Valderrama said that people often think about diversity in research as an ethical issue.

“Our argument is that it is also a scientific necessity. If we only study one part of the world, we risk misunderstanding how the microbiome shapes brain health.”

“Many of the world’s most informative microbiome studies have yet to be done. By studying populations experiencing different diets, environments and lifestyles, we may answer questions about the microbiome-gut-brain axis that simply cannot be answered in highly industrialised settings alone.” Professor Cryan added: “The microbiome gut brain axis has fundamentally changed how we think about mental health over the past 20 years.

“The next 20 years will depend on thinking globally. The greatest discoveries may come, not from studying more of the same populations, but from embracing the remarkable diversity of people.”

The authors outline their hope that the study will encourage funders, policymakers and researchers to build more equitable international partnerships and to recognise that understanding the biology of mental health requires studying the full diversity of human populations.