Diet with Low GI Index May Slow Progression of AMD: Study
People whose diet consists of foods that lead to a high glycemic index (GI) have a substantially higher risk of progression of age-related macular degeneration (AMD), according to recent long-term results from the Age-Related Eye Disease Study (AREDS).
In fact, consumption of highly refined carbohydrates can lead to an increased risk of AMD progression – up to 17 per cent – according to a poster presented at the annual meeting of the Association for Research in Vision and Ophthalmology (ARVO).
This newest set of results from AREDS confirms findings from earlier years, but shows that the effect of diet on AMD is even stronger than previously thought, according to Chung-Jung Chiu, PhD, assistant professor of ophthalmology at Tufts University.
Long-Term AMD Study
The AMD arm of AREDS is a long-term clinical trial sponsored by the US National Eye Institute, and involves more than 4,750 people who have at least early-stage AMD. Enrolment for the study began in November 1992 and ended in January 1998; participants were followed for at least five years.
For this recent analysis, data were based on findings from 3,977 participants, aged 55 to 80, who were at risk of progression of AMD. Patients were divided into groups according to the severity of their symptoms and asked to answer a questionnaire on their dietary habits. Researchers were then able to determine each participant’s overall dietary glycemic index.
They found that participants with a high glycemic index were on average 7.8 per cent more likely to have their AMD progress.
Education Needed on GI Risk
The findings are important because they show that keeping your GI low by dietary means can reduce the risk of AMD progression, says Dr Chiu. This study is also important because it highlights the role of diet in AMD, says Shweta Kaushik, a PhD candidate in the department of ophthalmology at the University of Sydney, Australia. She recommended that doctors educate patients about the glycemic effect of specific foods.
The Lowdown on Low-GI Foods
Foods that contribute to a lower dietary glycemic index include things such as legumes, rolled oats, basmati rice, whole bran, whole grains, and even pasta if it is cooked al dente (slightly hard). Foods that contribute to a higher glycemic index include things such as instant oatmeal, overcooked pasta, white bread, and many types of potatoes.
For more information, or before making any significant changes to your lifestyle or your diet, consult your eye doctor or your family physician.