Inflammation, particularly low-grade chronic inflammation, appears to affect several brain functions, from early brain development to the development of neurodegenerative disorders and perhaps some psychiatric diseases. On the other hand, nutrition and dietary components and patterns have a plethora of anti- and pro-inflammatory effects that could be linked to cognitive function. Even a modest effect of nutrition on cognitive decline could have significant implications for public health. This paper summarizes the available evidence regarding inflammation as a key mechanism in cognitive function and nutritional pro- or anti-inflammatory effects with the purpose of linking the apparent disparate disciplines of nutrition, immunity, and neurology.