Lowering Risk of a Major Eye Disease
By Rosalie Marion Bliss
Major U.S. dietary patterns are associated with the risk of developing an age-related eye disease, according to a study funded in part by the U.S. Department of Agriculture’s (USDA) Agricultural Research Service (ARS). Age-related macular degeneration (AMD) is a chronic, progressive eye-disease and is a leading cause of blindness among people aged 65 and older. For the dietary-patterns study, researchers analyzed existing data from a major federal clinical trial known as the age-related eye disease studies (AREDS).
The AREDS study was led by epidemiologist Chung-Jung Chiu at the Laboratory for Nutrition and Vision Research, which is headed by Allen Taylor, an expert in dietary means to delay age-related eye disease. The laboratory is at the Jean Mayer USDA Human Nutrition Research Center on Aging (HNRCA) at Tufts University in Boston, Massachusetts.
The macula is a 3-millimeter-wide group of light-sensing cells located near the center of the retina. As the eye ages, oxidized, damaged proteins and lipids—debris called “drusen”—begin to accumulate in the macula. This occurs when the damaged components are neither broken down by enzymes that control protein, lipid, and carbohydrate quality, nor detoxified via other mechanisms. Measurable drusen is one key indicator of AMD risk.
The team classified baseline data collected during AREDS on the eyes of more than 4,000 study volunteers into groups including little or no drusen, intermediate or large drusen, and advanced AMD. The researchers also analyzed the participants’ food-consumption data.
Two major food-intake patterns emerged from this analysis. Those who adhered to the “Oriental pattern” consumed relatively high intakes of vegetables, legumes, fruit, whole grains, tomatoes and seafood. Those who adhered to the “Western pattern” consumed relatively high intakes of red meat, processed meat, high-fat dairy products, French fries and refined grains.
The analysis showed that adherence to the Oriental pattern is associated with reduced odds of drusen and advanced AMD, and people who consumed the Western pattern had markedly increased odds. Read more about this research in the May 2015 issue of AgResearch magazine. ARS is the USDA's principal intramural scientific research agency.