Lutein may improve night vision

According to a new study from China daily lutein intake may improve sensitivity to contrast and glare, which helps driving at night.

In the randomized controlled trial, 120 healthy people who spent an average of 10 hours per day driving received either a daily dose of 20 milligrams of lutein or a placebo for one year (1). The participants’ visual acuity, serum lutein concentrations, macular pigment optical density (MPOD), and visual performance were measured at regular intervals. The study results showed that serum lutein levels, central MPOD, as well as contrast and glare sensitivity at night significantly improved in the lutein group, while no such changes were recorded in the placebo group. In addition, the lutein group showed a non-significant trend towards improved visual acuity.

The researchers concluded that supplementation with lutein may benefit driving at night and other spatial discrimination tasks carried out when ambient illumination is low. Although it is already known that lutein can affect visual performance, we still have much to learn about its effect in occupational populations, like dri-vers, they noted.

Lutein and zeaxanthin are the only carotenoids that filter the harmful blue light which can damage the rods and the cone cells in the eye. Cones are used for vision in well-lit conditions (photopic vision); whereas the eye switches over to the rods for seeing in very low-level light (scotopic vision). At many twilight levels (mesopic vision) a combination of rods and cones is used.

1. Yao Y. et al. Lutein supplementation improves visual performance in Chinese drivers: 1-year randomized, double-blind, placebo- controlled study. Nutrition. Published online January 2013.