Study Suggests Mediterranean Diet Is Associated with Better Psychological Well-being

Following a Mediterranean diet may provide additional benefits for mental health. A new study has now linked it to greater psychological well-being among people over the age of 50. The research is the result of a collaboration between University College London and the Barcelona Institute for Global Health (ISGlobal), a centre supported by the ”la Caixa” Foundation, and has been published in BMJ Open.

To date, numerous studies have shown that the Mediterranean diet—rich in fruits, vegetables, legumes, fish and olive oil—is an effective shield against physical decline and the development of disorders such as depression. However, this new study goes a step further by focusing on positive psychological well-being, which encompasses dimensions such as control, autonomy, pleasure and self-realisation, and includes questions relating to independence, enjoyment of life, sense of purpose, energy levels and future outlook. The study suggests that the benefits of following a Mediterranean diet for well-being are independent of the presence of depressive symptoms or the participants’ socioeconomic status.

The study analysed data from 3,296 individuals aged between 50 and 90 years who were participating in the English Longitudinal Study of Ageing (ELSA). Dietary habits were assessed between 2018 and 2019 using an online platform, where participants reported everything they had eaten and drunk on two non-consecutive days. Psychological well-being was evaluated through questionnaires administered on up to two occasions between 2018 and 2020.

Protection against the mental health effects of COVID-19

Data collected through the ELSA cohort show that the emergence of the COVID-19 pandemic and the restrictive measures that followed had a negative emotional impact on study participants. However, the decline in emotional well-being was less pronounced among individuals with greater adherence to the Mediterranean diet, suggesting a protective effect.

“Our study is observational and, therefore, the results should be interpreted with caution, since we cannot draw causal conclusions,” says Camille Lassale, ISGlobal researcher and senior author of the study. “Nevertheless, the questionnaires administered during the pandemic allowed us to follow participants over time, which is a major strength of the study. Although the biological mechanisms underlying the relationship between the Mediterranean diet and better mental health are still being investigated, the evidence suggests that its foundational foods and components help regulate key processes such as stress responses, inflammation, gut health and brain function”, she adds.

“This study provides further evidence of the relationship between what we eat and our mental health, an emerging field of research that we hope will generate substantial new evidence in the years to come,” says Alanna Shand, research psychologist and co-author of the study.

“Although many questions remain open, there is no doubt about the need to promote healthy lifestyles, prioritising a balanced diet rich in plant-based foods and low in foods such as processed meats and sweets, particularly among older adults,” says Andrew Steptoe, researcher at University College London and first author of the study.

Reference

Steptoe A, Shand AJ, Lassale C. Adherence to the Mediterranean diet and psychological wellbeing before and during the COVID-19 pandemic: a prospective analysis of the English Longitudinal Study of Ageing. BMJ Open. 2026; 16(6): e109599. http://dx.doi.org/10.1136/bmjopen-2025-109599