dGI is a scale used to determine how quickly carbohydrates are broken down into blood sugar, also known as blood glucose. Foods such as sweetened drinks, sodas and white bread are high-GI because they trigger a sharp rise and fall of blood sugar. Low-GI foods, such as whole grain versions of pasta and bread, have a milder effect on blood sugar response. Earlier data published by Taylor and Chiu suggests that daily substitution of five slices of whole grain bread for white bread out of a total intake of 250 g of carbohydrate might cut out almost 8% of advanced AMD over five years. This is readily achievable with little diet behavior modification.

Eating two to three servings of fatty fish such as salmon, tuna, mackerel, shellfish, and herring every week would achieve the recommended daily intake of DHA and EPA. However, the majority of AREDS participants and Americans eat a much lower level than recommended. "If changing dietary habits is not easy, supplementation is an option," says Chiu.

The authors stress it is still premature to conclude dietary recommendations for people with AMD and more studies are warranted. "Taken together, these data indicate that consuming a diet with higher levels of omega-3 fatty acids, antioxidants and low-GI foods may delay compromised vision due to AMD," says Taylor. "The present study adds the possibility that the timing of a dietary intervention as well as the combination of nutrients recommended may be important."

AMD is a progressive disease that attacks central vision, resulting in a gradual loss of eyesight and, in some cases, blindness. The NEI reports that AMD is the most common causes of non-remediable vision loss in Americans over 60.

tufts/