Lutein in patients with cataracts and age-related macular degeneration: a long-term supplementation study

Lutein, a non-provitamin A xanthophyll, is widely distributed in fruits and vegetables frequently consumed. In human serum, lutein is transported by lipoproteins and selectively accumulated in certain tissues (eg the retina). Epidemiological studies suggest that high intake and serum levels of lutein are associated with a lower risk of cataracts and age-related maculopathy. Subjects diagnosed with cataracts (CA; n = 5) or age-related macular degeneration (ARMD; n = 5) agreed to take three lutein capsules per week. Each capsule potentially provided about 12 mg of all-trans-lutein, 3 mg of 13/15-cis-lutein and 3.3 mg of alpha -tocopherol, as revealed by HPLC. Zeaxanthin was not detected. Average supplementation time was 13 months (range 4-20 months) for ARMD subjects and 26 months (range 16-36 months) for CA subjects. Blood samples for carotenoid analysis were collected every 3 months, coinciding with ophthalmological revision. In serum, concentrations of lutein, 13-cis-lutein and two ketocarotenoids increased significantly. Maximum increments were observed at 3-6 months, reaching levels above the 95th percentile of the reference population (>0.44 mu moll(-1)). Ophthalmological evaluation showed an average increment in visual acuity of 0.4, and glare sensitivity also improved. No significant side effects such as hypercarotenemia, carotenodermia or changes in biochemical or haematological profile were observed. Thus, lutein supplementation at achievable dietary levels increased and maintained serum lutein levels, which were associated with an improvement in the visual function of the patients. (C) 2001 Society of Chemical Industry.