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Close-up of the top of a glass filled with a liquid, green fruit, including grapes and kiwi, and a mint leaf.
Figure 17.1 Food ingestion, breakdown, absorption, and metabolism are critical to fuel the body for proper function. (credit: modification of work “Close-up, a glass of cocktail with green fruit and fresh mint” by Marco Verch/Flickr, CC BY 2.0)

To stay nourished, humans must ingest food, digest it into smaller usable substances, absorb what is digested into the body cells, and metabolize what is absorbed into usable energy. This chapter covers the expected overall normal findings, the meaning of abnormal findings, and the importance of nutrition in gut health. For detail regarding these processes and the ways to assess the gastrointestinal system properly for appropriate functioning, see The Digestive Process.

Consider this case: We will be following Zekia Azan, a 56-year-old Jamaican American woman with a history of Crohn’s disease. She has an average of five or six watery stools daily despite therapy for her disease. She comes to the outpatient clinic to be assessed after an exacerbation of her disease with increased diarrhea.


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