Certain Kinds of Fat Are Linked to Macular Degeneration

Macular degeneration is the leading cause of blindness in Americans over age 50. A study in this week’s "Archives of Opthalmology" finds a link between the disease and a diet high in saturated fats. For more about macular degeneration, we turn to Dr. Bernadine Healy, CBS News contributor and President of the American Red Cross.

What exactly is macular degeneration?

Let's take a look at where the problem begins. Macular degeneration occurs when the macula, which is responsible for central vision, becomes damaged. There are actually two types. The first and most common form is dry macular degeneration. Its progression is gradual. It is caused by aging and thinning of the tissues of the macula.

Wet macular degeneration is a much greater threat to vision loss, even though it accounts for only 10% of cases. With the wet form of the disease, new blood vessels grow beneath the retina where they leak fluid and blood and can create a large blind spot in the center of your visual field. If this happens, there will be a marked disturbance of vision.

What are the early signs that a person may have macular degeneration?

When looking straight at a newspaper, for instance, things would appear fuzzy directly in front of him, but the area around the image would be clear.

How is the condition diagnosed?

Your eye doctor will have you look at what is called an Amsler grid. Someone with the condition would see wavy lines which in fact are straight, and some patches of the grid would appear to be blank.

Do we know what causes macular degeneration?

Researchers have yet to pin down a specific cause. But what this study tells us is that there is a link between bad fats and the disease. People who took part in the study and ate foods such as chips, cookies and cakes were more likely to develop macular degeneration. What this study also tells us is that people who ate good fats, the omega-3 fatty acids found in fish such as salmon, were less likely to develop macular degeneration.

What treatment options are available?

Unfortunately, there is no cure. However, there are several treatment options available. For people with wet macular degeneration–which, again, is the more rare form–doctors are now using laser surgery in conjunction with intravenous drugs. But people need to know that this treatment has not been proven to reverse the damage of macular degeneration; rather, it delays further deterioration. Now for people with dry macular degeneration, the vision loss is typically not as severe and corrective lenses often can fix the problem.

You say there are other preventive steps that a person can take, besides staying away from fatty foods. Let’s go through a few:

• First, get regular eye exams. The American College of Ophthalmology recommends that everyone over 50 get his or her eyes examined every two years. People 65 an older should be going to their eye doctor every year. The sooner a diagnosis is made, the sooner a doctor can step in and consider what, if any, treatment would work best.
• Wear sunglasses. It's very important to protect your eyes from the sun's UVA and UVB rays. Some studies have suggested that prolonged or frequent exposure to UVA and UVB rays may also be a factor in macular degeneration and other eye conditions, so always wear sunglasses that block 99-100% of UV rays when outdoors.
• Quit smoking. We've known for years that smoking is bad for you, especially your heart and lungs, but a few years ago doctors identified cigarette smoking as a risk factor for macular degeneration because it inhibits blood circulation to the eyes.