A recent study conducted by the University of Reading, Roehampton University, FrieslandCampina (Netherlands), and Kings College London has found a link between poor diet quality and changes in brain chemistry associated with depression and anxiety. The research involved 30 volunteers and examined brain scans to compare neurotransmitter levels and grey matter volume in participants with different dietary habits. It was found that individuals with a poor diet had reduced levels of gamma aminobutyric acid (GABA) and elevated levels of glutamate, along with reduced grey matter volume in the frontal area of the brain, which is linked to mental health issues.
The research suggested that an unhealthy diet, high in sugar and saturated fats, can lead to imbalanced neurotransmission and reduced grey matter volume in the brain. This imbalance in frontal brain regions could explain the connection between diet and mental health conditions such as depression and anxiety. The study also highlighted a potential link between dietary patterns high in saturated fats and changes in glutamate and GABA production and neurotransmission, as seen in animal studies.
Furthermore, unhealthy diets were shown to impact glucose levels, leading to elevated blood glucose and insulin levels, which in turn increase glutamate in the brain and plasma, resulting in decreased GABA production and release. Changes in cell membranes caused by diets high in fat and cholesterol were also found to alter the release of neurotransmitters, potentially contributing to changes in brain grey matter volume observed in the study. These findings shed light on the complex relationship between diet, brain chemistry, and mental health outcomes.
The study also suggested that alterations in the gut microbiome due to high-saturated fat diets may play a role in affecting cell machinery that drives both GABA and glutamate production. A high-saturated fat, high-sugar diet was found to reduce the number of parvalbumin interneurons responsible for delivering GABA where it is needed, further highlighting the impact of diet on brain chemistry. These findings indicate the importance of maintaining a healthy diet for overall brain health and mental wellbeing.
Dr. Piril Hepsomali, lead researcher from the University of Reading, emphasized the significance of understanding the relationship between diet, brain chemistry, and mental health. It was noted that GABA and glutamate are also involved in appetite and food intake regulation, suggesting a potential circular relationship between eating well, having a healthier brain and mental wellbeing, and making better food choices to maintain overall health. This study underscores the importance of a balanced and nutritious diet in maintaining optimal brain function and mental health, and further research is needed to explore the mechanisms underlying these complex interactions.