Low GI Diet Protects Eyes

Age-related macular degeneration (AMD) is the most common cause of loss of vision in adults.

Last year, I wrote about a study that found a link between eating a diet relatively disruptive for blood sugar levels (a high-glycemic index diet) and increased risk of AMD. The authors of this study concluded that eating a low-glycemic index (GI) diet would perhaps eliminate 20 percent of cases of AMD.

I was interested to read a recent study that has replicated this finding. This particular research, conducted in Australia, assessed the relationship between dietary GI and risk of AMD over 10 years in a group of almost 2,000 people [1].

The results of this research showed that compared to individuals consuming lower-GI diets, those consuming the highest-GI diets were at a 77 percent increased risk of developing AMD. These findings are very much in line with those reported in the study from last year.

Eating a low-GI diet means eating a diet mainly of meat, fish, eggs, nuts, seeds, green vegetables, beans, lentils, and certain fruits such as apples and berries. My advice would be to limit grains, most bread, and many breakfast cereals. They are particularly disruptive to blood sugar and insulin levels when eaten in quantity.

This recent Australian research also looked at the relationship between cereal fiber intake and AMD risk. As the intake of these foodstuffs went up, risk of AMD generally went down. However, even in the individuals eating the most, the risk of AMD was not significantly lower statistically than those eating the least.

This should not be too surprising given that many grains can be quite disruptive to glucose and insulin levels, including some that are quite high in fiber (for example, whole-grain bread).

There are plenty of good reasons for eating a diet of relatively low-GI foods, including, most likely, a reduced risk of weight gain, type 2 diabetes, cardiovascular disease, and maybe some forms of cancer too. We now have evidence that suggests a lower-GI diet may help to protect against AMD and preserve vision as we age.

References:

1. Kaushik S, et al. Dietary glycemic index and the risk of age-related macular degeneration. American Journal of Clinical Nutrition 2008; 88(4): 1104–1110

Dr. John Briffa is a London-based physician and author with an interest in nutrition and natural medicine. Dr. Briffa's Web site

Last Updated
Nov 6, 2008