Abstract
Dietary carotenoids have attracted much attention because of their antioxidant activities and other biological activities including anti-cancer, anti-allergic, and anti-obese actions. Although no less than forty carotenoids are ingested under usual dietary habits, only several carotenoids and their possible metabolites have been found in human tissues. Little is known about the mechanism underlying the preferential accumulation of these carotenoids. Recently, facilitated diffusion mediated by scavenger receptor class B type 1 in addition to simple diffusion has been reported to mediate the intestinal absorption of carotenoids in mammals. Specificity of the receptor for carotenoids might cause selective absorption in intestine. The metabolism after intestinal absorption of carotenoids also affects their accumulation in tissues. This paper reviews the absorption and metabolism of carotenoids by introducing recent advances in this field.
