How are digestion and metabolism linked
Metabolism and digestion are two separate, but closely linked processes that are essential for the functioning of the body.
Digestion is the process of breaking down food into molecules that the body can absorb and use for energy and other functions. Digestion begins in the mouth, where food is mechanically ground by chewing and mixed with saliva that contains enzymes, thus initiating its chemical breakdown. The food then travels through the oesophagus to the stomach, where it is mixed with gastric juices that contain acid and enzymes for further breakdown. From the stomach, the partially digested food passes into the small intestine, where chemical breakdown continues with the help of enzymes from the pancreas and bile from the liver. The small intestine is where most of the nutrients are absorbed into the bloodstream. Undigested food residues pass into the large intestine, where water is absorbed and stool is formed, which is then excreted from the body.
Metabolism is the series of chemical processes in the body that are necessary to sustain life. It involves the breakdown of nutrients (catabolism) and the building of complex molecules (anabolism). Nutrients produced by digestion are the source of energy for metabolic processes. Through metabolism, we also regulate body temperature, growth, cell renewal and other functions. Digestion is responsible for converting food into energy that the body uses to perform functions such as breathing, movement, growth and cell renewal.
Digestion and metabolism are closely linked, as digestion breaks down food into smaller molecules that can be absorbed into the bloodstream and used in metabolic processes. In other words, digestion is the preparation of food for metabolism.
In turn, metabolism is dependent on the nutrients we get from digested food. Nutrients are essential for the energy, growth and repair of cells, and for the functioning of metabolic processes.
In short, digestion and metabolism are complementary processes that enable the body to obtain energy and nutrients from food and use them for its vital functions.
Sources:
- Rowland I, Gibson G, Heinken A, Scott K, Swann J, Thiele I, Tuohy K. Gut microbiota functions: metabolism of nutrients and other food components. Eur J Nutr. 2018 Feb;57(1):1-24. doi: 10.1007/s00394-017-1445-8. Epub 2017 Apr 9. PMID: 28393285; PMCID: PMC5847071.
- https://gi.org/patientnews/all-about-digestion-and-metabolism/
