What is the process by which the body breaks down food into smaller components?

The process by which the body breaks down food into smaller components is known as digestion. Digestion involves both mechanical and chemical processes that convert food into absorbable substances. During digestion, large, complex food molecules are broken down into simpler forms, such as carbohydrates into sugars, proteins into amino acids, and fats into fatty acids and glycerol. This breakdown occurs in various parts of the digestive system, including the mouth, stomach, and small intestine, where enzymes play a crucial role in facilitating these transformations.

Absorption, while related, refers specifically to the process by which the nutrients from the digested food are taken up into the bloodstream from the intestinal lining. Metabolism is a broader term that encompasses all chemical reactions in the body, including both the breakdown of nutrients for energy (catabolism) and the synthesis of necessary compounds (anabolism). Fermentation is a specific metabolic process typically associated with the breakdown of carbohydrates by microorganisms under anaerobic conditions, but it is not the main process responsible for digestion in the human body. Therefore, digestion is the correct term to describe the breakdown of food into smaller, usable components.