This study was published in the Journal of Nutrition 2006 Oct;136(10):2519-24
Study title and authors:
Consumption of one egg per day increases serum lutein and zeaxanthin concentrations in older adults without altering serum lipid and lipoprotein cholesterol concentrations.
Goodrow EF, Wilson TA, Houde SC, Vishwanathan R, Scollin PA, Handelman G, Nicolosi RJ.
Center for Health and Disease Research, Department of Clinical Laboratory and Nutritional Sciences, University of Massachusetts Lowell, MA 01854, USA.
This study can be accessed at: http://www.ncbi.nlm.nih.gov/pubmed/16988120
The lead author of the study, Elizabeth Goodrow, notes that lutein and zeaxanthin accumulate in the macular pigment of the retina, and are reported to be associated with a reduced incidence of age-related macular degeneration. A rich source of lutein and zeaxanthin in the American diet is the yolk of chicken eggs.
The objective of the study was to investigate the effect of egg consumption on the levels of lutein, zeaxanthin and cholesterol in individuals over 60 years of age. The study included 33 men and women who consumed one egg per day for five weeks.
The study found:
(a) Levels of lutein increased by 26% after five weeks of consuming one egg per day.
(b) Levels of zeaxanthin increased by 38% after five weeks of consuming one egg per day.
(c) Cholesterol levels were not affected throughout the study.
The findings of the study show that consuming one egg per day significantly increases levels of the carotenoids lutein and zeaxanthin.