The research, published in the American Journal of Clinical Nutrition, found that vegetarians and vegans were 30 to 40 per cent less likely to develop cataracts than meat-eaters.
“People who don’t eat meat have a significantly lower risk of developing cataracts,” said epidemiologist Naomi Allen of the University of Oxford, who co-authored the study.
Between 1993 and 1999, almost 30,000 people over the age of 40 were asked to fill out questionnaires about their diets. Researchers then monitored their medical records between 2008 and 2009 to see if they had developed cataracts. Almost 1,500 people had.
Those with particularly meat-heavy diets (more than 100g a day) were most at risk, with moderate meat-eaters only slightly less at risk. People who ate fish were 15 per cent less likely than hardcore carnivores to develop cataracts, with vegetarians and vegans at 30 and 40 per cent respectively.
By the time they are 80, more than 50 per cent of people will have been treated for cataracts.
Rather than showing the meat-eating causes the condition, however, the research suggests that consuming fruit and vegetables protects against it – and a generally healthy lifestyle may also play a part.