Abstract: The present disclosure relates generally to the supplementation of butyrate in the diet of mammals. Specifically, the present disclosure relates to a method for supplementing butyrate in the diet of a mammal resulting in improved physiological outcomes through the gut-brain axis, including improvements in anxiety and depression, and other cognitive behaviors, such as brain function, cognitive performance, executive function, stress, sleep, and focus. The present disclosure and methodology demonstrates advantages of administering a direct butyrate generating supplement, to influence the gut-brain axis through two pathways: a first pathway of butyrate generation leading to improvements in gut health which lead to improvements in brain health, and a second pathway of direct butyrate generation in the gut directly leading to improvements in brain health, independent of gut health.