The tertiary care pathway (TCP) for digestive health begins when 'alarm' or 'red flag' features have been excluded and the patient's quality of life is still significantly impaired. In this presentation, Dr. Anthony Hobson explores preliminary models of ingestion, digestion, fermentation and function, diagnostic testing in digestive health, and how to identify and use objective biomarkers of digestive health. This talk was presented at the SelectScience® Virtual Microbiology and Infectious Disease Summit 2022.