Nourishing Minds: Exploring the Impact of Diet on Mental Health and Cognition

Piril Hepsomali is a lecturer in psychology at the University of Reading. Her research interests include understanding affective and cognitive impairments associated with poor mental health and lifestyle factors, and how to improve these impairments using non-pharmacological approaches. Her recent publication, Adherence to unhealthy diets is associated with altered frontal gamma-aminobutyric acid and glutamate concentrations and grey matter volume: preliminary findings, examines the associations between diet quality and frontal cortex neurochemistry and structure. We were curious to hear more from Piril about her research, and the importance of nutrition in mental health.

Can you walk us through your research topics and what makes you passionate about it/what motivates you?

Of course! My research focuses on nutritional psychiatry/neuroscience across the lifespan. Specifically, I am trying to expand the scientific understanding of the complex interactions between diet/nutrients and mental well-being, sleep, and cognition, specifically focusing on their biological (e.g., inflammation) and neural (e.g., neurochemistry) correlates. In addition to this, I am also involved in undertaking clinical trials with nutritional interventions for mental, cognitive, and sleep health outcomes and related biomarkers in different population groups, such as children, healthy adults, older adults, and patients with mild cognitive impairment.

What gets me out of bed is understanding the biological mechanisms behind “you are what you eat” and the possibility of helping people with non-pharmacological dietary routes to improve their health and well-being.

Could you describe the take-outs of your recent publication?

We showed that individuals who adhere to low-quality diets have reduced frontal GABA and elevated frontal glutamate, as well as reduced frontal grey matter volume, compared to individuals who adhere to high-quality diets. Notably, we observed a significant negative association between rumination and frontal grey matter volume and a marginally significant association between rumination (a transdiagnostic factor for common mental disorders such as anxiety and depression) and frontal glutamate concentrations.

There was also a marginally significant association between frontal glutamate concentrations and frontal grey matter volume. Although this is a cross-sectional study and out findings should be confirmed in longitudinal studies, we believe that adhering to unhealthy dietary patterns may be associated with compromised GABA/Glutamate balance, and this could affect grey matter volume, and subsequently, ruminative thinking. In other words, we don’t have enough evidence yet to say, definitively, but all the evidence is pointing towards a significant role of diet, in mental health. The evidence suggests that eating well may support cognitive health through positive effects on brain chemistry and structure.

Based on your expertise, how important is the role of nutrition in mental health? In other words, can nutrition make a difference?

I believe that nutrition is as important as other determinants of mental health due to the bidirectional communication between the gut and the brain. Not only animal but also clinical research in different populations to date have shown that following a healthy dietary pattern may contribute to our mental well-being. And I am happy to say that research in this area is exponentially growing!

Research tells us about the important role of nutrition in brain development in the early years. What can you say about the importance of diet on good brain health in other stages of life?

I believe that diet/nutrition and other lifestyle factors, such as not being sedentary, and not smoking, are important regardless of where you are on the age continuum. Nutritional psychiatry/neuroscience research has been growing exponentially and highlighting the importance and role of nutrition in improving symptoms associated with common mental disorders in healthy young adults and/or in individuals with psychopathological conditions, as well as older adults with subjective memory complaints and/or dementia.

What can you say about the identification of dietary patterns or specific nutrients that can be linked to mental health?

I am very happy to answer this question as previous research indicates that some nutrients/foods might be beneficial for mental health in different populations, but it’s very important to highlight that we do not consume any particular food/foods and/or nutrient/nutrients in isolation. That is why in our research, we focused on dietary patterns – specifically the Mediterranean diet, which is characterised by high intakes of vegetables, fruits and nuts, legumes, unprocessed cereals, and low intakes of meat and meat products.

Some people may be aware of research behind omega-3 fatty acids, also as part of a Mediterranean diet, or the importance of a fibre-rich diet sometimes including prebiotic fibres. In that respect, could there be variations between different regions/countries across the globe?

Definitely. It is well known that cultural variability in food choice and eating practices exists. There is no (and there should not be) a “one-size-fits-all approach” when it comes to diet due to personal choices, geographical constraints, and other factors.

What type of research do you expect in the coming years for the field to move forward and obtain better insights into the relationship between nutrition and mental health?

The majority of research in this area is largely comprised of preclinical animal studies, so future research efforts should focus on the translation of the findings from animals to humans. Also, as cultural and personal variability in dietary intake exist, future research should focus on examining the comparative efficacy of different dietary patterns (e.g., Mediterranean diet; ketogenic diets; caloric restriction; traditional Japanese diets. etc.) which vary in macro- and micro-nutrient composition.

Curious to read the full research paper? You can do so here.