Macular Degeneration and Carbohydrate Intake
Can eating sweets lead to blindness?
There’s been some concern over this lately. That’s because a study of over 4000 people between the ages of 55 and 80 years old found that people with diets high in foods with elevated glycemic indices were more likely to develop or have signs of macular degeneration. The study is part of the Age-Related Eye Disease Study and was published in the American Journal of Clinical Nutrition. The researchers found that people who ate diets high in simple sugars and carbohydrates were more likely to have early eye changes that could lead to vision loss.
The study got a great deal of media attention. I would like to explain both parts of the study: Glycemic Index and macular degeneration.
Glycemic Index is a term used to explain the effect of carbohydrates on blood sugar. Dr. David Jenkins, a professor at the University of Toronto, Canada, is typically credited with developing the idea of Glycemic Index. His early work with Glycemic Index was published back in 1981 and focused on the prevention of diseases like diabetes and heart disease. Many researchers have expanded on Dr. Jenkins early work with the hope of understanding the effect of carbohydrates on blood sugar levels.
The Glycemic Index is a numerical value that is used to rank various foods. Typically, the scale is based on pure glucose as a reference point. The scale ranges from zero to 100, with pure glucose having a value of 100. The higher the Glycemic Index, the faster the carbohydrate is turned into glucose in the blood. Sugars and simple carbohydrates tend to have high glycemic indices. Interestingly, baked potatoes and white bread have higher glycemic indices than honey or table sugar (sucrose).
The concern over high blood sugar levels and high glycemic foods is related to insulin. Insulin is a hormone that your body releases to keep blood sugar levels from becoming too high. The problem with insulin is that too much can have detrimental effects around the body. Elevated insulin levels have been associated with the development of diabetes, heart disease, and abdominal obesity. Lots of high Glycemic Index foods and elevated insulin levels cause the release of lots of insulin which can drop the blood sugar levels too quickly and in turn cause fatigue, shakiness, and hunger that leads to a rollercoaster of sugar intake and insulin release.
The study found that people who ate diets with lots of high Glycemic Index foods had a higher risk of developing eye changes related to macular degeneration.
So what is macular degeneration? Macular degeneration, or age-related macular degeneration (AMD), is a disease that causes progressive blindness. The disease is associated with age and it gradually destroys central vision. Central vision is essential for reading, driving, and focusing on objects. AMD is the leading cause of vision loss in Americans over 50 years old. The risk of developing AMD is nearly 30 percent in people over 75 years old.
The most common early symptom is blurry vision and difficulty viewing details of objects. The diagnosis is typically made by an ophthalmologist or optometrist. Currently, there are no FDA approved treatments for AMD. However, there is strong scientific evidence that antioxidants like beta-carotene, lutein, zeaxanthin, vitamin C, vitamin E, omega-3 fatty acids, and zinc can help prevent and slow the progression of macular degeneration. The vitamins, minerals, phytonutrients, and antioxidants in the SuperFoods are ideal for preventing AMD. Actually, the author of the first two SuperFoodsRx books, Dr. Steven Pratt, is an ophthalmologist who sees the benefits of the SuperFoods in his AMD patients everyday.
The main factors that increase the risk of developing AMD:
1) Smoking
2) High Blood Pressure
3) Obesity
4) Family History and Genetics: Having a close family member with AMD puts an individual at higher risk for developing AMD
5) Caucasian Race: Whites are more likely to suffer from AMD than African-Americans
6) Female Gender: Women seem to have a higher risk than men
7) High Fat Diet
8) Poor Diet: Specifically, a diet deficient in antioxidants from Superfoods vegetables, (especially green leafy vegetables), fruits, nuts, and fish can increase an individual’s risk for developing AMD
9) High Carbohydrate/Glycemic Index Diet
Macular degeneration is not the first disease related to diets high in carbohydrates. Diets full of foods with a high Glycemic Index have been associated with the development of diabetes, cardiovascular disease, obesity, and even some cancers. Clearly, diets high in simple carbohydrates and sugars have an effect on many organs, including the eyes. When choosing to eat carbohydrates, choose whole grains. Eat your SuperFoods for ample antioxidants, and avoid foods with high sugar levels and elevated Glycemic Index numbers. Preventing macular degeneration is just one of the many benefits.