Retinol Activity Equivalent

**Semantic type:** Quantitative Concept

**Definition:** An arbitrary unit for measurement of the bioefficacy of ingested provitamin A carotenoids introduced by the U.S. Institute of Medicine (IOM). For a given amount of provitamin A compounds in a mixed diet, IOM estimates that the number of retinol activity e (RAE) is half the number of RE suggested by FAO/WHO. RAE is viewed as an approximate guideline because it was defined on the basis of relatively few studies and limited data on carotenoids bioavailability and bioconversion.

**Synonyms:** - RAE - RAE - Retinol Activity Equivalent (IOM) - Vitamin A Retinol - {RAE} - {RAE}