title: Changes in Macular Pigment Optical Density and Serum Lutein Concentration in Japanese Subjects Taking Two Different Lutein Supplements.
abstract: OBJECTIVE
  To investigate macular pigment optical density (MPOD) and serum concentration changes of lutein in Japanese subjects participating in a clinical trial in which two formulations of lutein and zeaxanthin supplements with different physiochemical properties are used.
  
  
  METHODS
  Thirty-six healthy volunteers were recruited into this prospective, randomized, parallel-group, double-masked comparative study at a single institute. Two products were used, FloraGLO® (Kemin Japan) and XanMax® (Katra Phytochem). The lutein particle size and zeaxanthin concentrations differed between the formulations. The subjects consumed one of the two supplements for a duration of up to 6 months. MPOD levels were measured by resonance Raman spectrometry at baseline and once a month until the end of the study. Serum lutein concentration was measured at baseline, month 3, and month 6. The subjects were also tested for contrast sensitivity, glare sensitivity, visual acuity, and in addition had a focal electroretinogram measured.
  
  
  RESULTS
  The mean serum lutein concentrations increased significantly after the first three months, but the mean MPOD levels in either supplement group did not show any statistically significant increase. A detailed analysis, however, revealed three response patterns in both groups for the increase of MPOD levels and serum lutein concentration, i.e. "retinal responders", who had an increase of both MPOD levels and serum lutein concentrations (n = 13), "retinal non-responders", who had only increased serum concentrations and no change in MPOD levels (n = 20), and "retinal and serum non-responders", who had neither MPOD level nor plasma concentration increases (n = 3). The subjects with low MPOD levels at baseline appeared to show increased MPOD levels at the 6 month time point upon lutein supplementation (r = -0.4090, p = 0.0133). Glare sensitivity improved in retinal responders in both supplement groups, while there were no remarkable changes in contrast sensitivity.
  
  
  CONCLUSIONS
  No statistically significant differences could be detected for MPOD levels and serum lutein concentrations between the two investigated lutein supplement formulations. Responses to lutein supplementation regarding MPOD levels and serum lutein concentrations varied between subjects. Subjects with lower MPOD levels at baseline responded well to lutein supplementation. However, since the number of subjects was low, a further study with more subjects is needed to prove that subjects with low MPOD levels will benefit from lutein supplementation.
  
  
  BACKGROUND
  UMIN-CTR UMIN000004593.
authors.affiliation: Department of Ophthalmology, Seirei Hamamatsu General Hospital, Hamamatsu, Shizuoka, Japan; Department of Medical Spectroscopy, Applied Medical Photonics Laboratory, Medical Photonics Research Center, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Obana
authors.affiliation: Department of Ophthalmology, Shimane University Faculty of Medicine, Izumo, Shimane, Japan.
authors.forename: Masaki
authors.initials: M
authors.lastname: Tanito
authors.affiliation: Department of Ophthalmology, Seirei Hamamatsu General Hospital, Hamamatsu, Shizuoka, Japan.
authors.forename: Yuko
authors.initials: Y
authors.lastname: Gohto
authors.affiliation: Department of Medical Spectroscopy, Applied Medical Photonics Laboratory, Medical Photonics Research Center, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan.
authors.forename: Shigetoshi
authors.initials: S
authors.lastname: Okazaki
authors.affiliation: Department of Physics and Astronomy, University of Utah, Salt Lake City, Utah, United States of America.
authors.forename: Werner
authors.initials: W
authors.lastname: Gellermann
authors.affiliation: Department of Ophthalmology and Visual Sciences, Moran Eye Center, University of Utah School of Medicine, Salt Lake City, Utah, United States of America.
authors.forename: Paul S
authors.initials: PS
authors.lastname: Bernstein
mesh_terms: D000328:Adult; D015350:Contrast Sensitivity; D019587:Dietary Supplements / Q000032:analysis; D005260:Female; D006801:Humans; D007564:Japan; D014975:Lutein / Q000008:administration & dosage / Q000097:blood* / Q000627:therapeutic use*; D008268:Macular Degeneration / Q000517:prevention & control*; D065348:Macular Pigment / Q000032:analysis / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D014792:Visual Acuity; D065146:Zeaxanthins / Q000008:administration & dosage / Q000097:blood* / Q000627:therapeutic use*
chemical_list: D065348:Macular Pigment; D065146:Zeaxanthins; D014975:Lutein