ABSORPTION OF BETA-CAROTENE AND OTHER CAROTENOIDS IN HUMANS AND ANIMAL-MODELS

Objective: To review available information on absorption and further m etabolism of different carotenoids in man and to discuss animal models and approaches in the study of carotenoid absorption and metabolism i n man. Conclusions: Humans appear to absorb various carotenoids in a r elatively non-specific fashion, but absorption kinetics and plasma tra nsport seem to differ among carotenoids, possibly because of differenc es in polarity. Absorbed beta-carotene for the most part is converted, mainly into retinyl eaters, but several details with respect to the c leavage reaction remain to be elucidated. Although interactions among carotenoids do exist, their importance and the mechanisms involved are still unclear. No animal model reflects the human situation for beta- carotene metabolism entirely. Thus, for every research question, the o ptimal model needs to be selected. Methods available for studying beta -carotene metabolism in man are limited. The most promising methods ar e the single dose-response in chylomicrons, and plasma responses after dosing with stable isotopes.