Abstract
The brain and the gut work synergistically with each other and other organs. Reviewing nutrition systemically (rather than by single organs) is a holistic way for dietitians to evaluate their clients' health status. Nutrition influences the genetic onset and consequences of many chronic diseases. With identification of up to 500 000 single nucleotide polymorphisms in an individual, the population-level potential for nutrigenomic optimization is astounding. The reader will be able to describe how several specific nutrients can maintain or improve health through supporting or suppressing gene expression.