Age-related cataracts (ARC) are the leading cause of acquired blindness in the US, but a new study published in the latest issue of Ophthalmic Epidemiology shows that antioxidant supplements may slow their progression.
The journal reported that the Roche European American Cataract Trial (REACT) had shown that a supplement containing beta-carotene and vitamins E and C slowed the progression of cataracts, the clouding of the lens in the eye which can lead to vision problems and ultimately blindness.
In the REACT study, the progression of lens clouding was significantly reduced in the supplemented group compared to those in the placebo group. Participants were given a supplement containing 750mg of vitamin C, 600 IU of vitamin E and 18mg of beta-carotene. This compares to current US intake levels of around 90mg of vitamin C, 9mg of vitamin E and less than 2mg of beta-carotene.
The cataract operation is the most common in the US, with more than two million carried out each year. One estimate suggests that a 10% reduction in cataract progression could reduce the number of cataract surgeries by 49%. The study's authors suggested that if subjects in the supplemented group continued their vitamin use over a 21-year period, they could achieve this 10% reduction.
While the REACT authors do not suggest that vitamin treatment would reduce the need for cataract surgery by 50%, they note that long-term use of antioxidant vitamins could have a "sizeable impact on the burden of providing cataract surgery for cataract-blind individuals."
REACT is a three-year clinical trial with 297 adults from the US and England. Participants were outpatients from ophthalmology clinics and had been already diagnosed with early ARC.