Esterification Does Not Impair Lutein Bioavailability in Humans

Abstract

Age-related macular degeneration (ARMD) is inversely associated with the accumulation of lutein + zeaxanthin in the macula, but higher lutein intakes are inconsistently related to reduced risk of ARMD in epidemiologic studies. Resolution of efficacy awaits clinical trials designed with knowledge of lutein supplement pharmacokinetics. Lutein bioavailability was determined for lutein diester and unesterified lutein formulations as they might be incorporated into dietary supplements. Healthy subjects (n = 18) consumed a single dose of each formulation (either 0.5 or 0.67 micro mol lutein/kg body, 10 and 8 subjects, respectively) in random order, and the appearance of free lutein + zeaxanthin was measured in serum from 0 to 408 h. Areas under the serum concentration x time curves (AUC), as a measure of bioavailability, were independent of gender, body mass index and lutein dose. The lutein diester formulation was 61.6% more bioavailable than the unesterified lutein formulation with higher mean AUC, maximum serum concentration and ascending slope (P < 0.05). The AUC was greater in 14 of 18 subjects when they consumed the lutein diester formulation. Comparison with data from previous studies suggested that dissolution was a greater limitation to bioavailability than lutein ester hydrolysis because an oil-solubilized unesterified lutein preparation, given at 0.5 micro mol/kg body, resulted in greater mean peak concentrations and AUC compared with either the unesterified or lutein diester formulations used in our study. In conclusion, the lutein diester formulation poses no impediment to lutein bioavailability at the doses tested, but formulation dissolution is an important factor in lutein bioavailability and should be evaluated before a supplement and dose are selected for use in clinical trials.

Effect of lutein and antioxidant dietary supplementation on contrast sensitivity in age-related macular disease: a randomized controlled trial

“…One study reported no significant difference in serum lutein response between 6 mg lutein from spinach, 6 mg pure lutein and 10.23 mg lutein esters (Chung et al, 2004). In another study, serum response was greater from lutein esters than pure lutein (Bowen et al, 2002). Although these studies suggest that the use of lutein esters in our formulation should not have hindered bioavailability, it is important to note that they recorded serum response rather than retinal response.…”

The Heritability of Macular Response to Supplemental Lutein and Zeaxanthin: A Classic Twin Study

“…It may be that the esterified form of L is more bioavailable. 43 It also is known that the bioavailability of L and Z is influenced by interactions with other dietary constituents (e.g., increased bioavailability when associated with lipid matrix, such as in egg yolks). 44 The fourth reason may relate to m-Z.…”

A physiological pharmacokinetic model describing the disposition of lycopene in healthy men

“…The initial 6 h rise was predicted by the flow of lycopene from the enterocyte to the chylomicron compartment, while the flow out of the fast-turnover liver pool into the lipoprotein compartment was associated with the second lycopene peak at 27 h. Two peaks in serum concentrations have also been observed for ␤-carotene by Kostic et al (45) and Novotny et al (16) following a single-dose administration. However, lutein and canthaxanthin, oxocarotenoids related to ␤-carotene, show only a single peak after dosing (45,46,47). These variations in serum response patterns could be related to the differences in rate of exchange of the polar versus apolar carotenoids between lipoproteins.…”