The impact of macular pigment augmentation on visual performance using different carotenoid formulations

Purpose. To investigate changes in macular pigment optical density (MPOD) and visual performance following supplementation with different macular carotenoid formulations. Methods. Thirty-six subjects (19 male, 17 female; mean ± SD, age 51 ± 13 years) were recruited into this single-masked placebo-controlled study, and were randomly assigned to one of the following three intervention (supplementation) groups: (1) group 1 (20 mg lutein [L] and 2 mg zeaxanthin [Z]); (2) group 2 (10 mg L, 2 mg Z, and 10 mg meso-zeaxanthin [MZ]); and group 3 (placebo). Outcomes measures included visual performance and MPOD response. Data were collected at baseline, at 3 months, and at 6 months. Results. At 3 and 6 months, a statistically significant increase in MPOD was found at all eccentricities (other than the most peripheral 3° location) in group 2 (P <0.05 for all), whereas no significant increase in MPOD was demonstrable at any eccentricity for subjects in groups 1 and 3. Statistically significant improvements in visual performance measures including visual acuity and contrast sensitivity with and without glare were observed for group 2 only. Only mesopic contrast sensitivity at one spatial frequency improved significantly by 6 months (P < 0.05) for group 1. No improvements in any parameters of visual performance were observed for subjects supplemented with placebo (P > 0.05 for all). Conclusions. These results suggest that supplementation with all three macular carotenoids potentially offered advantages over preparations lacking MZ, both in terms of MPOD response and visual performance enhancement.