A new study in the prestigious American Journal of Clinical Nutrition finds "a strong relation" between diet and incidence of cataracts, with "high meat eaters" at the greatest risk for the disease, while vegans are at the least risk. What are cataracts? Cataracts refers to "a clouding of the lens of the eye, which obstructs the passage of light and leads to vision loss if left untreated." The disease is "an important cause of low vision in both developed and developing countries," and "age-related cataract is responsible for 48% of the world's blindness."

Nepali teenage girl with bilateral cataracts. Photo courtesy of Seva Canada

About the study Previous studies of diet and cataract risk have focused on specific nutrients or healthy eating indexes but not on identifiable dietary groups such as vegetarians. Scientists recruited 27,670 healthy, non-diabetic participants in the UK to determine their diet as well as their rate of cataracts. Participants were divided into six diet groups, ranging from high-, medium-, and low-meat eaters, to fish eaters, vegetarians, and vegans. Results There was a strong relation between cataract risk and diet group, with a progressive decrease in risk of cataract in high meat eaters to low meat eaters, fish eaters (participants who ate fish but not meat), vegetarians, and vegans. After adjusting for several non-dietary factors such as age, smoking, ethnicity, and blood pressure, the results indicated a direct correlation between animal products in the diet and cataract risk. When compared to high meat eaters (people whose average daily meat consumption was 100 grams or more), fish eaters had a 20% lower risk for cataracts, vegetarians had a 30% lower risk, and vegans had a 40% lower risk of the disease. The study's authors, from the Nuffield Department of Clinical Medicine at the University of Oxford, concluded that, "Vegetarians and vegans had a significantly lower risk of cataract than did meat eaters, predominantly in the elderly, with a progressive decrease in risk in parallel with the amount of meat and other animal products in the diet." An abstract of the study, titled "Diet, Vegetarianism, and Cataract Risk" by Paul N. Appleby, Naomi E. Allen, and Timothy J. Key, was published online in advance of the print publication and is available to the general public for free.