of lutein, long-reported to have benefits for eye health, may also
protect against the detrimental effects of long-term computer display
light exposure, says a new study from China.
Improvements in the sensitivity to contrast on a computer screen were observed following 12 weeks of supplementation with lutein, according to findings of a study with 37 healthy subjects published in the British Journal of Nutrition.
Visual function in healthy subjects who received the lutein supplement improved, especially in contrast sensitivity, suggesting that a higher intake of lutein may have beneficial effects on the visual performance,” wrote the researchers from Peking University.
Lutein, a nutrient found in various foods including green leafy vegetables and egg yolk, has a ten-year history in the dietary supplement market as a nutrient to reduce the risk of age related macular degeneration (ADM).
The Beijing-based researchers recruited 37 healthy subjects aged between 22 and 30 with long-term computer display light exposure.
The participants were randomly assigned to one of three groups for 12 weeks: the control group (placebo – maltodextrin), or one of two lutein groups, (6 of 12 milligrams of lutein per day)
At the end of the test period, the researchers noted an increase in blood levels of lutein in both lutein groups, from 0.36 to 0.61 micromoles per litre, and from 0.33 to 0.73 micromoles per litre in the low- and high-dose groups, respectively.
While no differences were observed in terms of uncorrected visual acuity and best-spectacle corrected visual acuity, the researchers do report that there was a trend towards improved visual acuity in people in the high-dose lutein group.
Both lutein groups did experience improvements in measures of contrast sensitivity, said the researchers, with the improvements reaching statistical significance was in the high-dose group.
By Stephen Daniells, 02-Mar-2009
Source: British Journal of Nutrition
Published online ahead or print, First View article, doi:10.1017/S0007114508163000
“A 12-week lutein supplementation improves visual function in Chinese people with long-term computer display light exposure”
Authors: L. Ma, X.-M. Lin, Z.-Y. Zou, X.-R. Xu, Y. Li, R. Xu