The retinal carotenoid, lutein, is replenished through dietary intake along with zeaxanthin. Published studies have shown an inverse relationship between high dietary intake of these retinal pigments and the risk of age-related macular degeneration (AMD). A Recent report by researchers from Harvard University suggests that lutein may also play a protective role in the prevention of cataracts. The authors presented their work at the 1998 annual meeting of the Society for Epidemiologic Research in Chicago.

One etiology of cataract formation is the oxidation of lens proteins. Studies have shown that the antioxidant vitamins A, C and E are protective (see earlier EduFacts issues). Lutein is the only carotenoid found in the human lens. Since lutein does have antioxidant activity in the retina, the Harvard researchers hypothesized a similar role in the natural crystalline lens.

The authors evaluated 36,646 U.S. male professionals without previous diagnosis of cataract at the time of study intake in 1986. The cohort members were 45-75 years of age at that time. Dietary nutrient intake was assessed through a detailed questionnaire. Patients were followed 8 years. During 8 years 844 men had cataract extractions. After statistical adjustment for age, smoking, body mass index, alcohol consumption and other relevant covariants, the relative risk (RR) of cataract extraction for high lutein intake (highest quintile) versus the lowest intake (lowest quintile) was 0.82 (95% confidence interval of 0.66 - 1.03, p=0.03). This represents an 18% decrease in risk.

The authors concluded that lutein may help decrease the risk of cataracts requiring extraction.

References

• Brown L, Hankinson SE, Seddon JM, et. al. A Prospective Study of Carotenoid intake and Cataracts Among U.S. Men. (Abstract Number 213) Presented at the Annual Meeting of the Society for Epidemiologic Research, 1998, Chicago. Chicago..Illinois.