Abstract
Purpose: :
There is increasing evidence that suggests a possible beneficial effect of lutein and zeaxanthin on macular degeneration. Eggs, containing ample amounts of cholesterol, present themselves as a suitable vehicle to attain adequate absorption. We here present the results of a trial on the effect of daily egg consumption on plasma levels and macular pigment optical density (MPOD).
Methods: :
For this double blinded, three months interventional trial, 80 healthy subjects were recruited and randomized into 4 groups, stratified for age and gender. Group 1 consumed lutein-enriched eggs, group 2 zeaxanthin-enriched eggs, whereas group 3 had normal eggs daily. The control group 4 was not blinded and received no product. Serum lutein, zeaxanthin and MPOD were measured at baseline, week 6-7 and at endpoint. MPOD measurements were performed using the macular pigment screener (MPS), the macular pigment reflectometer (MPR), and a scanning laser ophthalmoscope (SLO).
Results: :
Baseline characteristics were comparable in the four groups. A regression analysis with serum lutein endpoint concentration as the dependent variable, and baseline serum lutein concentration and groups as the independent variables showed the lutein-enriched eggs to significantly increase lutein plasma levels (P<0.001). A similar analysis for zeaxanthin showed the zeaxanthin-enriched eggs to cause a significant increase of the plasma zeaxanthin concentration (P<0.001). A regression analysis of the SLO measurements with endpoint MPOD as dependent, and baseline MPOD and diets as independents showed a significant contribution of normal egg, lutein- , and zeaxanthin-enriched eggs as compared to the control group (P=0.044, P=0.019, and P=0.014 respectively). The MPR-lutein measurement also showed the lutein-enriched eggs to contribute to a significant increase in MPOD (P= 0.048).
Conclusions: :
In this study, we showed a significant effect of the lutein- and zeaxanthin-enriched eggs on the plasma concentrations of lutein, zeaxanthin, and MPOD. This result poses the enriched-eggs as an effective vehicle for the absorption of lutein and zeaxanthin.
Clinical Trial: :
www.clinicaltrials.gov NCT00527553
Keywords: clinical (human) or epidemiologic studies: treatment/prevention assessment/controlled clinical trials • macular pigment • age-related macular degeneration