Effects of formulation on the bioavailability of lutein and zeaxanthin: a randomized, double-blind, cross-over, comparative, single-dose study in healthy subjects.
OBJECTIVE
Lutein and zeaxanthin are macular pigments with a protective function in the retina. These xanthophylls must be obtained from the diet or added to foods or supplements via easy-to-use, stable formulations. The technique employed to produce these formulations may affect the bioavailability of the xanthophylls.


METHODS
Forty-eight healthy volunteers were randomized into this double-blind, cross-over study investigating the plasma kinetics of lutein provided as two different beadlet formulations. Subjects (n = 48) received a single dose of 20 mg of lutein as either a starch-matrix ("SMB", FloraGLO® Lutein 5 %) or as a cross-linked alginate-matrix beadlet ("AMB", Lyc-O-Lutein 20 %) formulation. Plasma concentrations of lutein and zeaxanthin were measured at 0, 1, 3, 6, 9, 12, 14, 24, 26, 28, 32, 36, 48, 72, 168, and 672 h.


RESULTS
The mean plasma AUC(0-72h), AUC(0-672h), and C(max) for total lutein and zeaxanthin and their all-E-isomers were significantly increased (p < 0.001) from pre-dose concentrations in response to SMB and AMB. There was no difference in lutein T max between the two test articles. However, by 14 h post-dose, total plasma lutein increased by 7 % with AMB and by 126 % with SMB. Total lutein AUC(0-72h) and AUC(0-672h) were 1.8-fold and 1.3-fold higher, respectively, for SMB compared to AMB. Both formulations were well tolerated by subjects in this study.


CONCLUSIONS
These findings confirm that the bioavailability of lutein and zeaxanthin critically depends on the formulation used and document a superiority of the starch-based over the alginate-based product in this study.
KGK Synergize, London, ON, Canada.
Malkanthi
M
Evans
Mareike
M
Beck
James
J
Elliott
Stephane
S
Etheve
Richard
R
Roberts
Wolfgang
W
Schalch
D000328:Adult; D000464:Alginates / Q000737:chemistry; D000975:Antioxidants / Q000008:administration & dosage* / Q000009:adverse effects / Q000737:chemistry / Q000378:metabolism; D018592:Cross-Over Studies; D019587:Dietary Supplements / Q000009:adverse effects; D004311:Double-Blind Method; D005260:Female; D005503:Food Additives / Q000737:chemistry; D020723:Glucuronic Acid / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry; D006801:Humans; D007700:Kinetics; D014975:Lutein / Q000008:administration & dosage* / Q000009:adverse effects / Q000031:analogs & derivatives / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009753:Nutritive Value; D012168:Retinal Pigments / Q000008:administration & dosage / Q000009:adverse effects / Q000737:chemistry / Q000378:metabolism; D013213:Starch / Q000737:chemistry; D013237:Stereoisomerism; D024341:Xanthophylls / Q000008:administration & dosage* / Q000009:adverse effects / Q000737:chemistry / Q000378:metabolism; D055815:Young Adult; D065146:Zeaxanthins
D000464:Alginates; D000975:Antioxidants; D005503:Food Additives; D006603:Hexuronic Acids; D012168:Retinal Pigments; D024341:Xanthophylls; D065146:Zeaxanthins; D020723:Glucuronic Acid; D013213:Starch; D014975:Lutein