What is the term for the process of breaking down food into usable nutrients?

Digestion refers to the complex process of breaking down food into smaller, absorbable components, such as nutrients. This process begins in the mouth, where mechanical and chemical actions start to break down food, and continues in the stomach and intestines, where enzymes and acids further disassemble food into its basic building blocks—carbohydrates, proteins, and fats. These smaller molecules can then be easily absorbed into the bloodstream for use by the body's cells.

While metabolism is related to how the body uses these nutrients, it encompasses a broader range of biochemical reactions, including anabolic and catabolic processes. Absorption specifically refers to the uptake of nutrients after digestion has occurred, while elimination denotes the removal of indigestible substances from the body. Thus, digestion is the correct term for the initial breakdown of food into usable nutrients.