Digestion in Biochemical Detail

For those interested in the latest biochemical breakdown of how the gastrointestinal (GI) tract digests food, beverages and other ingested substances, the June 2010 issue of Advances in Physiology Education features a Stay Current article (34(2):44-53) on the biochemistry of digestion by Barbara Goodman, Ph.D., a physiology professor in the Sanford School of Medicine at the University of South Dakota, Vermillion.

While most people simply assume that their GI tract will work properly to use nutrients, provide energy, and release wastes, few nonscientists know details about how various nutrients are digested and how the breakdown products traverse the cells lining the small intestine to reach the blood stream and to be used by the other cells of the body, she wrote, adding that there are recent discoveries of new transporters that appear to aid oligopeptide and fatty acid absorption, as well as further findings on the types of bonds enzymes hydrolyze.

While her self-stated goal in writing this Stay Current article is to keep physiology teachers up to date, the articles detailed flow charts and biochemical sequences could be useful to anyone working in the digestion arena (or anyone looking to enter this area of health). Of particular note, the flowchart/diagram for each macronutrientfats, carbohydrates and proteinsshow the breakdown and path of nutrients through to when the remaining compounds hit the blood stream. There is detailed information on enzymatic reactions and how various biochemicals are transported across various membranes and barriers.

A pdf of the article is available at the journals Web site.