Abstract: The association of high-fat diet (HFD) intake or western diet with obesity, diabetes, cardiovascular and other metabolic diseases has been demonstrated, and accumulating evidence has shown that HFD also has an important influence on the brain, behavior and cognitive functions. However, the mechanism for the effect of HFD on cognitive functions is not yet fully understood. In addition to insulin resistance, oxidative stress and inflammation, blood-brain barrier, brain-derived neurotrophic factor and serotonin pathway also play important roles in the mechanisms underlying cognitive impairment induced by HFD. In this article, we review recent research on the influence of diet (especially HFD) on cognitive functions and its possible mechanism of action in the brain, and we also summarize the site of action of HFD, with the aim to provide a good basis for targeted prevention and therapy of diet-related diseases and provide a useful guidance for future studies aimed to make our diet more reasonable.

Key words: high-fat diet, insulin, oxidative stress and inflammation, blood-brain barrier, serotonin