09.01.03
Indication: Absorption
Source: J Nutr, 2003;133:992-998.
Research: Researchers compared the absorption (in the blood and eye) of various doses of lutein and zeaxanthin, from 2.4 mg lutein, 5, 20 and 30 mg of lutein from lutein esters and 30 mg of zeaxanthin. Four experiments were reported, involving young, middle-age and elderly men and women. The amount of subjects in the experiments ranged from 2 to 21 and the duration of supplementation ranged from 60 days to 6 months.
Results: In response to taking lutein or lutein ester supplements, regardless of dosage, all subjects had increased blood levels of lutein. Many of the subjects also had increased eye levels of lutein (as measured by macular pigment optical density) and these subjects tended to be those who took the higher 30 mg dosage of lutein from lutein esters daily (rather than only 2.4 mg of lutein daily). There was considerable variability in lutein accumulation in the eyes, varying among individuals and, in some cases, varying between the eyes of the same individual. Zeaxanthin blood levels increased to a much lower extent compared to the same dose of lutein. Likewise, in the eyes of the two subjects taking the zeaxanthin supplements, accumulation of zeaxanthin was not as efficient as lutein.
Source: J Nutr, 2003;133:992-998.
Research: Researchers compared the absorption (in the blood and eye) of various doses of lutein and zeaxanthin, from 2.4 mg lutein, 5, 20 and 30 mg of lutein from lutein esters and 30 mg of zeaxanthin. Four experiments were reported, involving young, middle-age and elderly men and women. The amount of subjects in the experiments ranged from 2 to 21 and the duration of supplementation ranged from 60 days to 6 months.
Results: In response to taking lutein or lutein ester supplements, regardless of dosage, all subjects had increased blood levels of lutein. Many of the subjects also had increased eye levels of lutein (as measured by macular pigment optical density) and these subjects tended to be those who took the higher 30 mg dosage of lutein from lutein esters daily (rather than only 2.4 mg of lutein daily). There was considerable variability in lutein accumulation in the eyes, varying among individuals and, in some cases, varying between the eyes of the same individual. Zeaxanthin blood levels increased to a much lower extent compared to the same dose of lutein. Likewise, in the eyes of the two subjects taking the zeaxanthin supplements, accumulation of zeaxanthin was not as efficient as lutein.