Macular pigment and serum zeaxanthin levels with Goji berry supplement in early age-related macular degeneration

AIM: To evaluate the efficacy of Goji berry supplementation on improving macular pigment, serum zeaxanthin levels and visual acuity in patients with early age-related macular degeneration (AMD). METHODS: A total of 114 patients (aged from 51 to 92y, mean age 69.53 +/- 8.41y) with early AMD were enrolled in our prospective, randomized controlled study. The included patients were assigned randomly to the Goji group (n=57) with 25 g of Goji berries supplementation per day for 90d and the control group (n=57) with their normal diet for 90d. Macular pigment optical density (MPOD) was measured using heterochromatic flicker photometry (HFP). The levels of serum lutein (L)/zeaxanthin (Z) were analyzed using high-performance liquid chromatography (HPLC). MPOD, serum L/Z levels and best corrected visual acuity (BCVA) were recorded at baseline and 90d. RESULTS: In the Goji group, there were no statistically significant differences in the serum L levels between the baseline (0.199 +/- 0.149 mu mol/mL) and 90d (0.203 +/- 0.181 mu mol/mL) (t=-0.186, P=0.850); however the serum Z levels were increased at 90d (0.101 +/- 0.087 mu mol/mL) compared with those at the baseline (0.029 +/- 0.032 mu mol/mL) (t=6.412, P<0.001). Patients treated with Goji berry for 90d showed an elevated MPOD (0.877 +/- 0.202 DU) from the baseline (0.731 +/- 0.205 DU) (t=-4.741, P=0.000). In contrast to the control group, the serum Z levels and MPOD were higher in the Goji group at 90d (both P<0.05). At 90d, patients with Goji berry supplementation had a relative decrease in BCVA (0.21 +/- 0.18 logMAR) compared with the baseline (0.27 +/- 0.20) (t=2.397, P=0.020). CONCLUSION: Overall, daily supplementation with Goji berry for 90d improves MPOD by increasing serum Z levels rather than serum L levels in early AMD patients. Goji berry may be an effective therapeutic intervention for preventing the progression of early AMD.