Vision: Vitamin E Benefit for Cataracts in Dispute

By NICHOLAS BAKALAR
Many studies, including one reported in this column in February, have suggested that vitamin E supplements help prevent cataracts. But a large 10-year randomized trial, the longest to date, has found no difference in cataract formation between those who took vitamin E and those who did not.
The study, in the May issue of Ophthalmology, included 37,675 women without an initial diagnosis of cataracts. Half took 600 international units of vitamin E on alternate days; the rest took a placebo. Neither the subjects nor the researcher knew who was taking which pill. The participants filled out annual questionnaires to monitor the pill taking, adverse effects and cataract formation.
At the end of the study, there was no difference in the number of cataracts between the groups and no difference in the types of cataracts they developed. Nor did those with possible risk factors like age and cigarette smoking get any benefit from vitamin E.
“Although observational data tend to suggest benefits for vitamin E,” said William G. Christen, the lead author and an associate professor of medicine at Brigham and Women’s Hospital, “data from this more rigorous randomized 10-year trial suggest little benefit.”
The good news is that the study detected no harmful effect from the moderately high dose of vitamin E.