Excessive red meat may affect vision, say researchers

Melbourne, March 19: According to researchers, a diet with high concentration of red meat harms the sight by clogging up blood vessels in the retina and the choroid, which can reduce the flow of oxygen and nutrients necessary for vision.

The research team led by Elaine Chong from the Centre for Eye Research Australia at the University of Melbourne found an association between people who ate red meat more than 10 times a week and early Age Related Macular Degeneration (AMD).

The researchers said: “A high level of red meat consumption may be a risk factor for early AMD, or act as a marker for a group of people with an increased risk from other lifestyle factors.”

To evaluate associations between red meat intake and AMD, the authors conducted a cohort study of 6,734 persons aged 58–69 years in 1990–1994 in Melbourne, Australia. They then assessed the consumption of meat and meat products on the basis of a questionnaire.

According to the analysis, the researchers observed that people who consumed red meat at least ten times per week were 47 percent more likely to suffer from early-stage AMD, as opposed to people who ate red meat perhaps five times or less in a week.

Another aspect highlighted was that the risk doubled for those who eat lots of processed meats like salami and sausage. However, in people who consumed more than 31/2 meals of chicken, the chances of suffering from a late form of age-related macular degeneration actually decreased. The team found them to have a 57 percent lower risk of late-stage AMD than people consuming chicken less than 1.5 times per week.

Dr Elaine Chong reflected that people should be aware of how much red meat they eat. "Everything in moderation is the answer," she said.

AMD is the leading cause of blindness among older people, and diet has been postulated to alter risk of this ailment. AMD is a degenerative retinal disease that causes central vision loss and leaves only peripheral vision. Early detection can help in treatment and rehabilitation.

Although nearly 25 to 30 million people globally are troubled by AMD, the exposure to this condition is fairly low. The condition reduces central vision and affects one in seven people aged over 50. The AMD Alliance International has projected the incidence to be on the rise and triple by 2025.

The study is another blow to the meat industry. Previous studies have linked consumption of red meat with certain cancers and cardiac problems. According to a recent survey commissioned by the World Cancer Research Fund, 10 percent of health conscious people have cut down on processed meat intake.

Dr Chong declared that "This is the first study that has really looked at meat intake and macular degeneration, so I would not push for a public health warning until further studies to confirm the findings."

The findings are published in the American Journal of Epidemiology.