Drug Interactions between beta-carotene and lutein / zeaxanthin

Coadministration of lutein and beta-carotene may alter the intestinal absorption of both compounds. The mechanism of interaction is unknown. In eight healthy volunteers administered lutein and beta-carotene simultaneously, the area under the serum concentration-time curve (AUC) of lutein was reduced by approximately 40% to 45% compared to control values, while beta-carotene AUC was reduced 35% to 69% in five subjects but increased 3- to 5-fold in three subjects. Lutein enhanced beta-carotene AUC only in subjects with low absorption of beta-carotene when administered alone. In another study, lutein was found to decrease the intestinal absorption of beta-carotene in 12 healthy male volunteers, whereas lycopene had no significant effects. The clinical significance of these changes has not been established.