Bioavailability of lutein from vegetables is 5 times higher than that of beta-carotene

Background: To gain more insight into the relation between vegetable consum ption and the risk of chronic diseases, it is important to determine the bi oavailability of carotenoids from vegetables and the effect of vegetable co nsumption on selected biomarkers of chronic diseases. Objective: To assess the bioavailability of beta-carotene and lutein from v egetables and the effect of increased vegetable consumption on the ex vivo oxidizability of LDL. Design: Over 4 wk, 22 healthy adult subjects consumed a high-vegetable diet (490 g/d), 22 consumed a low-vegetable diet (130 g/d), and 10 consumed a l ow-vegetable diet supplemented with pure beta-carotene (6 mg/d) and lutein (9 mg/d). Results: Plasma concentrations of vitamin C and carotenoids (ie, alpha-caro tene, beta-carotene, lutein, zeaxanthin, and beta-cryptoxanthin) were signi ficantly higher after the high-vegetable diet than after the low-vegetable diet. In addition to an increase in plasma beta-carotene and lutein, the pu re carotenoid-supplemented diet induced a significant decrease in plasma ly copene concentration of -0.11 mu mol/L (95% CI: -0.21, -0.0061). The respon ses of plasma beta-carotene and lutein to the high-vegetable diet were 14% and 67%, respectively, of those to the pure carotenoid-supplemented diet. C onversion of beta-carotene to retinol may have attenuated its plasma respon se compared with that of lutein. There was no significant effect on the res istance of LDL to oxidation ex vivo. Conclusions: Increased vegetable consumption enhances plasma vitamin C and carotenoid concentrations, but not resistance of LDL to oxidation. The rela tive bioavailability of lutein from vegetables is higher than that of beta- carotene.