Submitted to: American Journal of Clinical Nutrition
Publication Type: Peer reviewed journal
Publication Acceptance Date: 12/15/2003
Publication Date: 2/12/2004
Citation: Molldrem, K., Li, J., Simon, P.W., Tanumijardjo, S. 2004. Lutein and beta-carotene are bioavailable in humans from lutein-containing yellow carrots. American Journal of Clinical Nutrition. 80:131-136. Interpretive Summary: We have developed novel carrots with yellow color, rather than the familiar orange types. The yellow pigment, lutein, is important for eye health, but it was not known if humans could absorb lutein from yellow carrots. Nutrients are often much less bioavailable from complex foods like carrots than from food supplements. In this study we fed nine 23 to 28 year old human subjects both yellow carrots and lutein dietary supplements. Lutein from carrots was 65% as bioavailable as it was from daily supplement, which is a high value compared to bioavailability for other nutrients from complex foods. This information is important for carrot growers, nutritionists, dieticians, and consumers since it indicates that yellow carrots are a rich source of dietary lutein.
Technical Abstract: Background: Lutein is one of the hydroxy carotenoids constituting the macular pigment of human retinas. Increasing lutein intake from foods may increase the density of this pigment and decrease risk for developing macular degeneration. Yellow carrots are a novel food source that could increase lutein consumption. Objective: The objective was to evaluate and compare lutein uptake and clearance in humans from genetically selected yellow lutein carrots fed chronically and from a lutein supplement. Design: Four women and 5 men, aged 23-28 y, participated in this randomized, blinded, 3 x 3 crossover study. Intervention treatments consisted of yellow carrot (YC, 1.7 mg lutein/d), white carrot as a negative control (WC, 0 mg lutein/d), and a lutein supplement in oil as a positive control (LS, 1.7 mg lutein/d). Each treatment lasted 7 d, followed by a 7-d wash-out period. Results: Serum lutein concentration changes were + 0.31 ± 0.08, + 0.19 ± 0.08, and - 0.04 ± 0.04 µmol/L for LS, YC and WC treatments, respectively. Area under the curve for 0 to 14 d (AUC0-14d) analysis showed highly significant (P < 0.0001) differences between treatment groups. Lutein from the yellow carrots was relatively 65% as bioavailable as the lutein from the supplement. AUC0-14d analysis for -carotene (-0.01 + 0.28 mol . d/L) also revealed that YC maintained serum -carotene concentrations at 0.35 ± 0.30 µmol/L while LS did not (AUC0-14d = -0.71 ± 0.59 mol . d/L). Conclusions: Lutein from this novel food source results in a significant increase in serum lutein concentration and does not result in the decline in -carotene that accompanies administration of lutein supplements.