Decreased antioxidant levels increase risk of age-related macular degeneration with exposure to sunlight

The journal Archives of Ophthalmology recently reported that having reduced plasma antioxidant levels and increased exposure to sunlight increases the risk of neovascular, or advanced age-related macular degeneration (AMD).

In a recent study (titled the European Eye Study), over 4,400 participants over age 65 were analyzed for the presence of macular degeneration. Their blood plasma was evaluated for vitamins C and E, the carotenoids lutein and zeaxanthin, and the mineral zinc. Each individual also completed a questionnaire regarding their typical exposure to sunlight. This was used to estimate blue light exposure from visible light, which is known to contribute to the development of macular degeneration. Early stage macular degeneration was detected in 2,182 participants, and 101 had the advanced form of the disease. The research found no association between blue light exposure and early macular degeneration.

However, among participants in the lowest quartile (25 percent) of serum vitamin C, zeaxanthin, vitamin E and zinc, exposure to blue light significantly increased the risk of advanced macular degeneration.

Arch Ophthalmol 2008 Oct;126(10):1396-403

Lutein and zeaxanthin may improve visual performance and reduce the effects of glare

Healthy subjects with an average age of 23.9 were assigned to receive daily supplements of lutein (10 mg) and zeaxanthin (2 mg) for six months. The subjects' eyes were then tested for the effects of glare as experienced in everyday situations, including being outdoors on bright days, lengthy sessions of looking at a computer monitor, and nighttime exposure to oncoming headlights.

Following six months of supplementation, the participant's average macular pigment optical density (MPOD) increased significantly from the average value at the beginning of the study. MPOD is a measure of the eye's ability to filter short-wave light.

After testing the subjects for their performance in visual tasks following glare, researchers concluded that four to six months of supplementation with lutein and zeaxanthin significantly reduced the detrimental effects of the exposure and improved visual performance.

Optom Vis Sci 2008 Feb;85(2):82-8