June 4, 2018

Discover what foods to eat to prevent macular degeneration and fend off vision loss.

 

More than 2 million Americans face vision loss from age-related macular degeneration. However, new research links a low-glycemic diet with halting the development of certain signs of the disease.

According to the Centers for Disease Control and Prevention, in older individuals, age-related macular degeneration is the leading cause of impairment on close-up vision, the kind we need for reading and driving.

“Age-related macular degeneration is usually a slow decline in central vision as we age,” said Christine Rust, M.D., an ophthalmologist at the Vanderbilt Eye Institute. “This is due to a degradation or atrophy of the cells responsible for our central vision as we get older. In some patients, they begin to not work as well, and then those cells die.”

Although there are two forms of age-related macular degeneration, wet and dry, most people have the dry form. This type currently has no effective treatment and no methods for delaying its progression. Rust said the Tufts study is encouraging for demonstrating that a healthy diet could keep the retina in better shape, but she recognizes the need for more research.

In the study, researchers fed groups of mice the same number of calories but altered the types of carbohydrates. Some mice were fed a low-glycemic diet, while others were fed a high-glycemic diet. Mice on the high-glycemic diet developed signs of retinal damage. Researchers did not observe significant retinal changes in the mice on the low-glycemic diet, however. After six months, some of the mice that were on the high-glycemic diet were switched to the low-glycemic diet, and the change stopped or reversed age-related macular degeneration.

“While the mice in this study had reversal of their retinal degeneration,” Rust said, “I find it hard to believe that switching to a low GI diet would reverse any signs of AMD in our patients. However, it is possible that having a good, healthy low GI diet can slow the progression of AMD, but this would need to be studied more in depth.”

A low-glycemic diet is characterized by only eating carbohydrates that are low on the glycemic index, in addition to other foods. The glycemic index is a measure of how fast a carbohydrate raises your blood sugar (glucose). Low GI foods cause blood sugar to rise slower than high GI foods. By giving you more control over your blood sugar, a low-glycemic diet can help you lose weight or lower your risk for heart disease and type II diabetes. The index gives foods a ranking of 0 to 100. You can start eating a lower-glycemic diet by making simple changes. Try quinoa instead of rice, for example.

  • Low GI: 55 and below (soy products, rolled oats, beans, most fruits, milk, lentils)
  • Moderate GI: 56 to 69 (quick oats, whole-wheat bread, brown rice)
  • High GI: 70 and above (potatoes, white bread, instant oatmeal, pineapple)

“I always tell my patients, the healthier you are as a whole, the healthier your eyes will be,” Rust said. “Having a good diet, controlling any blood pressure, cholesterol or blood sugar issues, plus wearing sunglasses are the best things you can do for your eyes to keep them healthy and prevent eye complications like AMD, diabetic retinopathy and cataracts.”

The bottom line: While there’s no guarantee that switching to a low-glycemic diet will stave off age-related macular degeneration, it could be worth it for overall better health.

The Vanderbilt Eye Institute assesses and treats a variety of conditions at various locations in Middle Tennessee, including Hendersonville.