Researchers here note a correlation between glycemic index, a measure of the impact of carbohydrate content of food on blood glucose, and risk of suffering age-related blindness. Given the comparatively large influence of calorie intake over all aspects of health and metabolism, and the composition of the typical modern diet, I think one has to consider the usual suspects of total overall calories consumed, visceral fat, and chronic inflammation before moving on to look at things like the contribution of diet to cross-links in the eye or lipofuscin formation in the retina.
Extending healthful life is a millennia-old dream and objective. During the intervening centuries a multitude of concoctions and remedies have been offered, usually with few substantiated results. During the last century it was demonstrated that limiting caloric intake is associated with extended life in many mammals, albeit results remain to be clarified in humans. A myriad of modeling studies have revealed signaling pathways that are associated with life extension and the last two decades have seen an interest in the types of dietary carbohydrates that might confer health advantage, and possibly longevity.
Loss of vision due to age-related cataracts or age-related macular degeneration is widely prevalent, affecting about 85% and 15% of the elderly respectively. With centenarians among the fastest growing segments of societies, and with loss of vision a very costly personal and societal burden, there is keen interest in extending vision - that is, delaying age-related macular degeneration and cataract - or diminishing risk for these debilities. Using extensive epidemiologic and nutritional information from the Nurses' Health Study and Age-Related Eye Disease Study (AREDS) we determined that measures of total carbohydrate, and even more so, glycemic index (GI), are associated with visual health. We also modeled this relationship in mice in order to elucidate etiologic relationships between dietary glycemia, visual health, and genetics.