A study published in Investigative Ophthalmology & Visual Science shows that lutein and zeaxanthin—compounds contained naturally in green, leafy vegetables, such as kale and spinach—supplementation may improve the ability for young, healthy people to see under glare conditions.
The randomized, double-blind and placebo-controlled study took place at the University of Georgia in Athens over the course of 12 months.In the study, approximately 100 young and healthy subjects were assessed and received daily dosage levels of 10 mg of FloraGLO lutein and 2 mg of Optisharp zeaxanthin, or a placebo over a one-year supplementation period. Macular pigment optical density (MPOD) and serum levels of lutein and zeaxanthin increased significantly in the supplemented group, while no changes were noted in the placebo group. The macula is the yellow spot in the central retina that is responsible for detailed central vision and the yellow color is the result of high concentrations of lutein and zeaxanthin. Macular pigment optical density is a measure of the amount of macular pigment present in the macula and has been shown to have a major impact on visual performance. The study looked at three aspects of visual performance: glare disability, photostress recovery time, and contrast enhancement. Glare disability is the amount of glaring light that can be tolerated by a person before vision is severely impaired. Photostress recovery time determines how fast the eye can recover sight after experiencing a flash of bright light, while contrast enhancement is the ability to detect chromatic borders that allow discrimination of an object from its colored surroundings. The results of the study demonstrate significant improvement in these aspects of visual performance and add to the growing body of evidence to support the role of lutein and zeaxanthin in helping to achieve optimal visual performance and comfort. "Showing lutein and zeaxanthin improve function in normal healthy individuals widens its applications, as we continue to investigate the potential of nutrition to support both eye health and visual performance," said Billy Hammond Jr., the principal investigator of the study, University of Georgia in Athens.