Roy J. Hardman¹*, Greg Kennedy¹, Helen Macpherson², Andrew B. Scholey¹ and Andrew Pipingas¹

The Mediterranean-style diet (MedDiet) involves substantial intake of fruits, vegetables, and fish, and a lower consumption of dairy, red meat, and sugars. Over the past 15 years, much empirical evidence supports the suggestion that a MedDiet may be beneficial with respect to reducing the incidence of cardiovascular disease, cancer, metabolic syndrome, and dementia. A number of cross-sectional studies that have examined the impact of MedDiet on cognition have yielded largely positive results. The objective of this review is to evaluate longitudinal and prospective trials to gain an understanding of how a MedDiet may impact cognitive processes over time. The included studies were aimed at improving cognition or minimizing of cognitive decline. Studies reviewed included assessments of dietary status using either a food frequency questionnaire or a food diary assessment. Eighteen articles meeting our inclusion criteria were subjected to systematic review. These revealed that higher adherence to a MedDiet is associated with slower rates of cognitive decline, reduced conversion to Alzheimer’s disease, and improvements in cognitive function. The specific cognitive domains that were found to benefit with improved Mediterranean Diet Score were memory (delayed recognition, long-term, and working memory), executive function, and visual constructs. The current review has also considered a number of methodological issues in making recommendations for future research. The utilization of a dietary pattern, such as the MedDiet, will be essential as part of the armamentarium to maintain quality of life and reduce the potential social and economic burden of dementia.

Neurocognitive Aging and the Potential Associated Risk Factors

An aging population raises the potential for increased incidence of cognitive impairment (1). Preservation of brain function and the reduction of risk of neurological disorders have become key issues for society. In addition to the need to find treatments for disorders, such as Alzheimer’s disease (AD), it is becoming increasingly apparent that early intervention is critical for the maintenance of brain health across the life span and reducing the risk of accelerated neurocognitive decline (2). There is mounting evidence that risk factors for cardiovascular disease, stroke, diabetes, and other later-life chronic health conditions also exacerbate age-associated cognitive decline, which can lead to AD (3). Research is increasingly focusing on understanding how interventions, such as improving nutritional status and modifying risk factors that may impinge directly and/or indirectly on brain functioning, can reduce the risk of neurocognitive impairment (4). Closer adherence to a traditional Mediterranean-style diet (MedDiet) may be beneficial and protective with respect to addressing such risk factors, ultimately reducing the rate of cognitive decline (5).