What term refers to vitamin-containing substances that are converted to the actual vitamin once they are in the body?

The term that refers to vitamin-containing substances that are converted to the actual vitamin once they are in the body is "precursors." Precursors are compounds that the body can transform into active forms of vitamins through biochemical processes. For example, beta-carotene is a precursor to vitamin A; the body converts it into retinol, the active form of the vitamin needed for various physiological functions.

Coenzymes are organic molecules that assist enzymes in catalyzing biochemical reactions, but they are not substances that convert into vitamins. Prebiotics are non-digestible food ingredients that promote the growth of beneficial microorganisms in the intestines, thereby supporting gut health, rather than being related to vitamin conversion. Catalysts are substances that accelerate a chemical reaction without being consumed in the reaction itself, and while they are important in biochemical processes, they do not refer to vitamin precursors. Understanding these distinctions can help clarify the role of precursors in nutrition and metabolism.