Wednesday, October 10, 2007

Glycemic Index & Eye Health

Researchers concluded, in a recent study published in the American Journal of Clinical Nutrition, that consuming foods high on the glycemic index can increases the risk of developing age-related macular degeneration (AMD).

The glycemic index is a measurement of the extent to which foods raise blood sugar levels. Past studies have suggested a link between diets containing high-glycemic-index foods and a higher risk of heart disease and diabetes.

Scientists from the Center on Aging at Tufts University obtained dietary information from 4,099 non-diabetic participants ages 55-80 years (56 percent women) in the Age-Related Eye Disease Study (AREDS). A total of 8,125 eligible eyes at baseline were classified into 1 of 5 AMD groups according to the size and extent of pathological growths known as drusen, the presence of atrophy, and neovascular changes.

Compared with subjects who consumed lower glycemic-index foods, subjects who consumed foods with the highest glycemic index had a significantly higher risk of developing drusen-related damage associated with AMD. Consuming foods with a high-glycemic index also appeared to increase the severity of AMD. For subjects who consumed more high-glycemic foods than the average person their age, there was a 49 percent increase in the risk of advanced AMD.

The study authors concluded that “20% of prevalent cases of AMD would have been eliminated if the AREDS participants consumed diets with a dietary glycemic index below the median.” They went on to state that “a reduction in the dietary glycemic index, a modifiable risk factor, may provide a means of diminishing the risk of AMD.”

This is very important news!


Ann said...

What foods should we eating to .
prevent macular degeneration?

Ellen Troyer, MT MA said...

Good question!

A well balanced diet that includes plenty of protein, fats and a fairly limited amount of low glycemic carbs (keeping fiber needs in mind), including lots of dark green vegetables like spinach and kale.

Remember all those high glycemic carbs quickly metabolize to sugar and that adds fat to our bodies which hoards lutein and zeaxanthin so these xanthophyll cartenoids can't become the pigment that protects our macula from UV light. Excess body fat is also eventually responsible for elevated triglycerides which we associate with heart and liver disease.

Google "glycemic index" and you will find lots of sites that give you the glycemic rating for most foods.

Mable Swant said...

It seems that my eye health is connected to my overall body health, if I read this blog and your Friday Pearls correctly.

Why doesn't my eye doctor talk about this during my exams? I'm 35 pounds overweight and the subject of my weight and what I eat, or the vitamins I take, has never been mentioned by my eye doctors.

Do you think they are afraid to discuss my weight because they think it might embarrass me, or do you think they just don't care about me?

I take your Oculair every day because my mother and my sister have macular degeneration. I stumbled on your web site and spent over an hour reading the scientific rationale pages for all your products. I have never seen such detailed information on a vitamin company web site.

Who are you people and why aren't your vitamins in Costco?

Kristen T said...

I love this blog and the way you use your answers to questions and comments to teach us stuff.

I'm telling all my friends to tell their parents to "google alert" the Biosyntrx blog.

Anonymous said...

What percentage of carbs do you think our daily diet should include?

Ellen Troyer, MT MA said...

Our orthomolecular nutritional biochemist board member, Steve Whiting, PhD, usually suggests 25-30 percent of a normal persons diet consist of low glycemic carbs (mostly veggies, just a few fruits, quality grains, and almost NO sugar).

He also always recommends high quality full-spectrum multiples to supply the nutrients that are lost in our food supply due to harvesting early, cold storage, chemical ripening and other processes that affect the nutrient content of fresh, frozen and canned vegetables and fruits.

The good news is that he also says "eat one piece of cake if you really want it and get it over with because you can't possibly develop healthy eating habits while you are focused on how much you want a piece of white cake."