The study by Tufts University found that for the same amount of total carbohydrate, high GI foods release sugar into the bloodstream more rapidly than low GI foods.
This can affect your eyesight by causing damage to the retina.
High GI foods include potatoes, white bread and rice, while examples of low GI foods are whole grains, lentils and fruit.
The researchers discovered that a high GI diet triggered the development of many features of AMD.
These included the loss of function of cells at the back of the eye, and of the cells that capture light.
However, eating a low GI diet did not.
Interestingly, switching from a high GI diet to a low GI diet could repair this damage to the retina.
Sheldon Rowan, scientist at Tufts University and lead study author, said: “We were genuinely surprised that the retinas from mice whose diets were switched from high- to low-glycemic index diets midway through the study were indistinguishable from those fed low-glycemic index diet throughout the study.
“We hadn’t anticipated that dietary change might repair the accumulated damage in the RPE so effectively.
“Our experimental results suggest that switching from a high-glycemic diet to a low-glycemic one is beneficial to eye health in people that are heading towards developing AMD.”
AMD happens gradually over time – in the early stages it causes blurred vision, while later on it can develop into blindness.
There is currently no cure, making these new findings of particular interest.
The researchers also believe they’ve found potential biomarkers of AMD which can be used to predict when a person is at risk for this disease.
Allen Taylor, scientist at Tufts University and senior study author, said: “Currently, there are no early biomarkers to anticipate the disease. Our findings show an interaction between dietary carbohydrates, the gut microbiome, specific biochemical molecules, and AMD features.
“This work should lead to new approaches to understand, diagnose and treat early AMD – perhaps before it affects vision.
“Already anticipated by our human epidemiologic studies, the findings imply that we can develop dietary interventions aimed at preventing the progression of AMD, a disease which impacts millions and costs billions worldwide.”