Neural Correlates of Eating Habits and Nutritional Behaviors in the General Population: A Systematic Review of Observational Studies

Eating habits and nutritional behavior impact brain structures and lifestyle modification, yet their bidirectional relationship with neural structures remains underexplored. This review aimed to shed light on this complex relationship in the brain-behavior axis by reviewing publications that have examined the relationship between eating habits, nutritional behaviors, and their neural correlates.

For this review, three databases of Scopus, PubMed, and Web of Science were primarily searched. Twenty-one English-language original papers published up to January 2025 were ultimately included focusing on the general population (healthy individuals covering all age groups) and magnetic resonance imaging (MRI) as the neuroimaging modality.

Healthier eating habits, such as the Mediterranean diet and high fish intake, were positively associated with brain volumes, microstructures, and cortical surface areas. Conversely, less healthy eating habits, like the Western diet, were linked to reductions in brain structures, particularly in the hippocampus and gray matter. Specific eating behaviors, such as restrained eating and enjoyment of food, showed significant associations with changes in brain structures. The impact of dietary patterns on brain structures varied by age and gender, with some diets showing protective effects against brain atrophy and white matter hyperintensities.

This systematic review emphasizes the significant associations between eating habits, nutritional behaviors, and brain structures. Future research should focus on identifying underlying mechanisms and developing personalized dietary interventions coupled with brain stimulation to promote brain health and prevent cognitive decline.