Table 2.
Intervention studies on the effects of lutein on visual performance.
| Study (year) | Design (Number of Participants) | Intervention and Lutein Supplementation | Effects |
|---|---|---|---|
| AREDS2 (2013) [27] | RCT, participants with bilateral drusen or AMD in 1 eye (4176); 4 groups: G1 (1007); G2 (1038); G3 (1062); G4 (1069) | G1: AREDS formulation; G2: AREDS + L 10 mg + Z 2 mg; G3: AREDS + DHA 350 mg + EPA 650 mg G4: AREDS + L 10 mg + Z 2 mg + DHA 350 mg + EPA 650 mg |
No effect in reducing progression to advanced AMD. No effect in improving VA. In the lowest quintile of L dietary intake, L + Z had significant effect vs. no L + Z in reducing progression to advanced AMD. |
| AREDS2 (2014) [105] | RCT, participants with bilateral drusen or AMD in 1 eye (3335 eyes analyzed); 3 groups: G1 (1114 eyes); G2 (1104 eyes); G3 (1117 eyes) | G1: AREDS + L 10 mg + Z 2 mg without beta-carotene; G2: AREDS + L 10 mg + Z 2 mg; G3: AREDS formulation |
G1 (compared to G3) significantly reduced progression to advanced AMD and neovascular AMD, no effect for CGA. No difference between G2 vs. G3. |
| Akuffo et al. (2015) [92] | Intervention trial, participants with AMD (67); 3 groups with different dosages | G1: L 20 mg + Z 2 mg; G2: L 10 mg + Z 2 mg + MZ 10 mg; G3: L 3 mg + Z 2 mg + MZ 17 mg |
After 3 years, all the groups showed a significant increase in MPOD but no effects in reducing progression to advanced AMD or improving VA. CS significantly increased, mainly in G3. |
| Beatty et al. (2013) [15] | RCT, participants with at least bilateral early AMD (433); intervention group (216) vs. placebo (217) | Intervention group: formulation containing L 12 mg | No significant improvement in CS. Significant VA enhancement not before 24 months. |
| Berrow et al. (2013) [26] | RCT, participants with AMD (14); treatment group (8) vs. no treatment (6) | Treatment group: L 12 mg | After 40 weeks, no clinical effects; only minimal improvement in mfEGR. |
| Bone (2010) [38] | Intervention trial, healthy participants (87); 4 groups: G1 (10); G2 (17); G3 (22); G4 (38) | G1: placebo; G2: L 5 mg;G3: L 10 mg; G4: 20 mg | MPOD increased in a linear, dose-dependent manner. L did not increase MPOD in all the participants. |
| Cangemi (2007) [101] | Intervention trial, participants with at least 1 eye with dry AMD (37) | Formulation containing L 8 mg | Significant improvement in VA after 6 months. |
| Dawczynski et al. (2013) [35] | RCT, participants with non-exudative AMD (145); 3 groups: G1 (50); G2 (55); G3 (40) | G1: L 10 mg + Z 1 mg + DHA 100 mg + EPA 30 mg; G2: L 20 mg + Z 2 mg + DHA 200 mg + EPA 60 mg; G3: placebo |
Significant increase in MPOD and improvement in VA both in G1 and G2; MPOD decreased in G3. No significant differences in MPOD accumulation between G1 and G2. |
| Fujimura et al. (2016) [96] | Intervention trial, participants with at least 1 eye with wet AMD or early AMD (20) | Formulation containing L 20 mg + Z 1 mg + DHA 200 mg | After 6 months, significant increase in MPOD and CS. Linear correlation between MPOD and serum concentrations of L. |
| Hammond et al. (2014) [97] | RCT, healthy participants (115); intervention group (58) vs. placebo (57) | Intervention group: formulation containing L 10 mg + Z 2 mg | After 1 year, significant increase in MPOD, recovery from photostress and chromatic contrast. |
| Huang et al. (2015) [94] | RCT, participants with early AMD (108); 4 groups: G1 (28); G2 (26); G3 (27); G4 (27) | G1: placebo; G2: L 10 mg; G3: L 20 mg; G4: L 10 mg + Z 10 mg |
After 2 years, significant increase in MPOD and mean retinal sensitivity. |
| Huang et al. (2015) [36] | RCT, participants with early AMD (108); 4 groups: G1 (28)]; G2 (26); G3 (27); G4 (27) | G1: placebo; G2: L 10 mg; G3: L 20 mg; G4: L 10 mg + Z 10 mg |
After 2 years, significant increase in MPOD and CS, no effect in VA and flash recovery time. Same efficacy in all treatment groups. |
| Ma et al. (2009) [23] | Intervention trial, healthy participants (37); 3 groups: G1 (12); G2 (12); G3 (13) | G1: placebo; G2: L 6 mg; G3: L 12 mg |
After 12 weeks, no effect in improving VA and glare sensitivity. CS significantly increased in both G2 and G3, but much more in G3. |
| Ma et al. (2012) [37] | RCT, participants with early AMD (108); 4 groups: G1 (27); G2 (27); G3 (27); G4 (27); group of healthy controls (36) | G1: placebo; G2: L 10 mg; G3: L 20 mg; G4: L 10 mg + Z 10 mg |
After 48 weeks, both G3 and G4 effectively increased MPOD; CS only improved on G3. Positive correlation between MPOD increase, VA and CS. Significant dose-response effect following L supplementation. |
| Murray et al. (2013) [16] | RCT, participants with early AMD (72); intervention group (36) vs. placebo (36) | Intervention group: formulation containing L 10 mg | Significant effect on MPOD. No improvement in VA, but VA decreased on placebo. Changes in VA were significant between L and placebo. |
| Nolan et al. (2011) [98] | RCT, healthy participants (121); intervention group (61) vs. placebo (60) | Intervention group: formulation containing L 12 mg + Z 1 mg | After 1 year, significant effect on MPOD but no improvement in VA, CS, glare disability, recovery from photostress. |
| Obana et al. (2015) [25] | RCT, healthy participants (36) | L 10 mg + Z 1 mg | After 6 months, no effect on MPOD. Only a subgroup of 13 participants had an effective increase both in serum levels of L and MPOD. |
| Parisi et al. (2008) [13] | RCT, participants with non-advanced AMD (27); treatment group (15) vs. no treatment [12] | Treatment group: formulation containing L 10 mg + Z 1 mg | After 1 year, significant improvement in central retina dysfunction but no effect in peripheral retina. |
| Piermarocchi et al. (2012) [102] | Intervention trial, participants with dry AMD [109]; treatment group [84] vs. no treatment [26] | Treatment group: formulation containing L 10 mg + Z 1 mg | Significant improvement in VA and CS after 2 years. |
| Richer et al. (2004) [12] | RCT, participants with atrophic AMD (90); 3 groups: G1 (29); G2 (30); G3 (31) | G1: L 10 mg; G2: formulation containing L 10 mg; G3: placebo |
After 1 year, both G1 and G2 showed significantly increased MPOD, VA and CS. |
| Richer et al. (2011) [95] | RCT, participants with non-advanced AMD (60); 3 groups: G1 (10); G2 (25); G3 (25) | G1: L 9 mg; G2: Z 8 mg; G3: L 9 mg + Z 8 mg |
After 1 year, both G1 and G2 showed effectively increased MPOD and CS; no improvement in G3. |
| Rosenthal et al. (2006) [22] | Intervention trial, participants with AMD (45); 3 groups: G1 (15); G2 (15)]; G3 (15) | G1: L 2.5 mg; G2: L 5 mg; G3: L 10 mg |
After 6 months, no effect in VA. 10 mg were safely administered without toxicity or adverse events. |
| Sabour-Pickett et al. (2014) [100] | Intervention trial, participants with AMD (52); 3 groups: G1 (17); G2 (21); G3 (14) | G1: L 20 mg + Z 2 mg; G2: L 10 mg + Z 2 mg + MZ 10 mg; G3: L 3 mg + Z 2 mg + MZ 17 mg |
After 1 year, MPOD increased in all groups; the significant improvement in CS was much more effective in G3. |
| Sasamoto et al. (2011) [24] | Intervention trial, healthy controls (5), participants with AMD (33) and participants with central serous chorioretinopathy (5) | Formulation containing L 6 mg | After 1 year, no effect in MPOD. Significant improvement in CS and retinal sensitivity. |
| Stringham et al. (2016) [34] | RCT, healthy participants (28); 4 groups: G1 (5); G2 (7); G3 (8); G4 (8) | G1: placebo; G2: L 6 mg + Z 0,7 mg + MZ 0,5 mg; G3: L 10.9 mg+Z 1.3 mg + MZ 0.9 mg; G4: L 22 mg + Z 2.7 mg + MZ 2 mg |
All the intervention groups showed a significant effect in MPOD at 12 weeks, G3 was much more effective. |
| Weigert et al. (2011) [14] | RCT, participants with AMD (126); 2 groups: G1 (84); G2 (42) | G1: L 20 mg for the first 3 months, L 10 mg for the last 3 ones; G2: placebo | After 6 months, MPOD increased by nearly 28% vs. placebo in G1. No improvement in VA and macular function. The lower MPOD at baseline, the greater the improvement. Linear correlation between changes in MPOD, VA and macular function. |
| Wolf-Schnurrbusch et al. (2015) [99] | Intervention trial, participants with AMD (79); 2 groups: G1 (40); G2 (39) | G1: formulation containing L 10 mg + Z 1 mg; G2: formulation containing L 10 mg + Z 1 mg + DHA and EPA 130 mg |
After 6 months and 1 year, MPOD and CS [not VA] significantly increased G1. No significant effect on G2. |
| Yao et al. (2013) [93] | RCT, healthy participants (120); treatment group (60) vs. placebo (60) | Treatment group: L 20 mg | After 1 year, significant improvement in MPOD, CS and glare sensitivity vs. placebo. No effect in VA. |
AMD: age-related macular degeneration; AREDS: age-related eye disease study (formulation: vit. C: 500 mg; vit. E: 400 UI; beta carotene: 15 mg; zinc: 80 mg; copper: 2 mg); CS: contrast sensitivity; DHA: docosahexaenoic acid; EPA: eicosapentaenoic acid; L: lutein; mfEGR: multifocal electroretinogram; MPOD: macular pigment optical density; MZ: meso-zeaxanthin; RCT: randomized controlled trial; VA: visual acuity; Z: zeaxanthin.