Lutein Improves Visual Function in Patients with Age-Related Cataracts

Reference:
  Olmedilla B, Granado F, Blanco I, Vaquero M. Lutein, but not ?-tocopherol, supplementation improves visual function in patients with age-related cataracts: a 2-y double-blind, placebo-controlled pilot study. Nutrition 2003;19:21-4.

Design: 
  Randomized, double-blind, placebo-controlled

Participants:
  Fifteen male and female patients (55-73 years) with a clinical diagnosis of cataracts (mostly subcapsular and nuclear opacities).

Study Medication and Dosage:
  Patients were randomized to receive lutein (15 mg), ?-tocopherol (100 mg) or placebo-one capsule three times per week. Capsules were prepared by Quest International (Unilever, Vlaardingen, The Netherlands).

Duration:
  Twenty-four months 
   
Outcome Measures:
  Visual function was measured with routine static (visual acuity) and dynamic (glare sensitivity) every three months. In addition, serum carotenoids and vitamin status were measured every three months.

Key Findings:
  There was a significant improvement in visual acuity compared to baseline only in the lutein group (p < 0.005), whereas there was a trend towards the maintenance of and decrease in visual acuity with ?-tocopherol and placebo supplementation, respectively. Compared with baseline measurements, the final levels of glare sensitivity at low, medium, and high thresholds also improved in the lutein group while there was no change in the ?-tocopherol and placebo groups. There was no progression in cataracts in four of five subjects in the lutein group, three of five in the ?-tocopherol group and one of five in the placebo group. No significant adverse events were observed in any subjects in this study. Serum concentration of lutein and ?-tocopherol increased in their respective group, although statistical significance was reached only in the lutein group. No changes in serum concentration of these nutrients were observed in the placebo group. Maximum serum concentrations of lutein and ?-tocopherol were observed, on average, at 3 to 6 months after onset of treatment.

Practice Implications:
  This interesting clinical trial suggests that 45 mg of lutein per week (roughly equivalent to 6.5 mg/day) may safely and effectively improve visual function in patients with age-related cataracts. It should be noted that 7 mg of lutein is also contained in 100 g of spinach and that the serum concentrations found in this trial have been obtained from 60 g of spinach consumption daily. While the number of patients in this trial were too few for meaningful statistical comparison by group, the trial supports the findings of earlier trials suggesting that lutein (and also zeaxanthin) is an important nutrient for macular pigment density and its inverse correlation with lens density.