Abstract
Presentation Description :
Results from human observational studies and large, long-term trials provide evidence of the impact of individual nutrients and other food components on disease onset and progression. They strengthen the body of evidence contributed by results of experiments in cells and animals and small human trials, which is necessary to draw inferences about the benefit and safety of nutritional recommendations to patients.
A broad and deep body of evidence suggests that diets rich in fruits and vegetables slow the processes known to promote age-related macular degeneration and glaucomatous neurodegeneration, such as oxidative stress, inflammation and metabolic stress. Such diets are also rich in the carotenoids lutein and zeaxanthin, which selectively concentrate in the neural retina where they protect against light damage, and lower oxidative stress and inflammation. For some components (such as lutein and zeaxanthin) the benefit of supplemental intake may be greatest in individuals with low dietary intake. There is inadequate evidence about the levels of intake in supplements that can be safely consumed over long periods of time.
A consistent body of evidence suggests that the intake of fatty fish from cold waters (which contain high levels of long chain omega-3 fatty acids, rich in membranes of the neural retina) lowers risk for AMD, but the evidence for a benefit of supplements is inconclusive. While animal research suggests that supplementation with long chain omega- 3 fatty acids may slow optic nerve degeneration, data from large cohort studies do not currently support this benefit.
Observational studies suggest better status of vitamins D and B12 are related to low risk for AMD, but results are inconsistent. A small, but emerging body of evidence suggests higher odds of glaucoma in individuals with poor vitamin D status, but prospective studies are needed. Supplementation may be important, despite a lack of conclusive evidence, because a substantial number of adults may be at risk for poor status of these vitamins. For vitamin D, this might be particularly important in individuals living in extreme northern or southern hemispheres, who do not consume food sources of vitamin D (such as fish, egg yolk and fortified milk). This is because in winter there is inadequate ultraviolet B light to catalyze the synthesis of this nutrient in the skin.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.