Caloric restriction, physical activity, and cognitive performance: A review of evidence and a discussion of the potential mediators of BDNF and TrkB

Lifestyle behaviours, such as eating and physical activity (PA), have been recognised as factors that may influence age-related cognitive decline. A high-fat diet and sedentary behaviour have been associated with poor cognitive performance in a variety of domains, in both animals and humans, while caloric restriction (CR) and PA are typically associated with positive outcomes. The lifestyle-associated changes in cognitive performance typically involve areas of the brain that are vulnerable to structural alterations, such as the hippocampus. Here, we frame age-related cognitive change in regard to the brain and cognitive reserve theories and discuss the potential for CR and PA interventions, independently and in combination, to affect cognitive trajectories. We provide mechanistic support for these interventions to affect cognitive performance through BDNF and its high-affinity receptor TrkB. Further, we offer suggestions for future study designs to investigate these relationships and urge researchers to be mindful of the potential mediating roles of BDNF and TrkB.