Antioxidants in Diet Linked to Cataract Risk

December 31, 2013

By Kathryn Doyle

NEW YORK (Reuters Health) Dec 31 - Women who eat foods rich in antioxidants may have a lower risk of cataracts as they age, according to a new Swedish analysis.

"Oxidative damage of the eye lens caused by free radicals has been suggested to be crucial in development of cataract," said Susanne Rautiainen of the Institute of Environmental Medicine at the Karolinska Institutet, who led the study.

Her team looked at the diets of more than 30,000 middle aged and older women, and found those with the highest total intake of antioxidants had about a 13% lower risk of developing cataracts than women who consumed the least.

"Previous studies have focused on individual antioxidants obtained from the diet or supplements and they have reported inconsistent results," Rautiainen said. "However, in diet much wider ranges of antioxidants are present than those studied previously."

Instead of looking at single antioxidants, such as vitamins C and E, and plant flavonoids such as lycopene, the researchers used a measure of total antioxidant values in foods, which takes into account how they work together.

For the study, more than 30,000 Swedish women over age 49 were observed for about 7 years for signs of developing cataracts, and were given a dietary questionnaire.

Foods high in antioxidants include coffee, tea, oranges, whole grains and red wine. Based on total antioxidant consumption, the researchers divided the women into quintiles. Among those who consumed the most antioxidants, 745 cases of cataract were recorded, compared to 953 cases among women with the lowest antioxidant consumption.

Women who ate more antioxidants also tended to be more educated and were less likely to smoke, the authors reported online December 26 in JAMA Ophthalmology.

"The results are not that surprising," said William Christen of Brigham and Women's Hospital and Harvard Medical School in Boston.

Christen, who studies eye diseases and vitamins and was not involved in the new study, said the findings are in line with previous research suggesting antioxidants may help protect against cataracts, but the study has limitations, he cautioned.

"The women participants simply reported on a questionnaire the food choices they made over the past year," Christen said. "As an observational study, there is always concern that women who choose healthier diets may also differ in other important ways, like body weight, smoking habits, aspects of the diet other than antioxidants, that may be more directly related to cataract risk."

Rautiainen suspects the results would be similar among men and in other countries, but can't say for sure until those studies have been done.

"Results of numerous observational studies have suggested a possible beneficial role for high antioxidant intake in a number of age-related disorders," Christen said. But in most randomized controlled trials, which would better isolate the effects of antioxidants alone, the link has not held up, he said.


JAMA Ophthalmology 2013.


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.