Vitamin A: Retinoids and Carotenoids To truly understand vitamin A it is important to understand all the different terminology, the different derivatives and precursors including carotenoids. Last Update: May 11, 2019 October 30, 2018 2003Technical DocumentsRelated Knowledge Base Posts -Pepti-HyaluronicRejuvenator SeriesHow Peptides May Influence the Health of our Skin