Scientists are learning new ways that people can protect themselves against the age-related disease macular degeneration (AMD), which is the most common cause of blindness for people over the age of 60. Surprisingly, for a certain subset of people, one of the most promising protective strategies may be to simply donate blood a few times a year!

What’s the Connection?

According to Julian Nussbaum, MD, chair of the department of ophthalmology at the Medical College of Georgia, studies suggest that iron overload contributes to the “wet” or most dangerous form of macular degeneration. Dr. Nussbaum believes that excessive iron wreaks havoc by infusing the blood with too much oxygen, which then stimulates the growth of extraneous blood vessels.

Here’s how: The macula (the part of the eye that enables you to see fine detail) is located in the center of the retina, the light-sensitive tissue at the back of the eye. The retina converts light into electrical impulses that the optic nerve sends to the brain. With wet AMD, abnormal blood vessels, which are fragile and prone to leaking, start to grow behind the retina. This leads to “macular degeneration” and, therefore, to vision loss.

Dr. Nussbaum based his iron-overload hypothesis on earlier research done by a colleague at Medical College of Georgia, Vadivel Ganapathy, PhD, professor and chair of biochemistry. Dr. Ganapathy found extra blood vessel growth in mice bred to have hemochromatosis (a condition that leads to overabsorption of iron). The mice developed a form of “wet” macular degeneration similar to human AMD.

Dr. Nussbaum and his research team are now collecting blood samples in people over age 60 — both with and without macular degeneration — to see how many have the gene mutation that causes hemochromatosis. Their ultimate goal is to develop a simple screening test for hemochromatosis and related macular degeneration risk.

What to Do?

AMD is most common among women of all races and Caucasian men. Other risk factors include smoking, being overweight and having a family history of AMD. If you are at risk, it is important to do all that you can to protect your vision…

Take omega-3 fatty acids. Consider supplementing with anti-inflammatory omega-3 fatty acids from fish oil, shown to be helpful in preventing AMD in people at risk.

Eat lots of green leafy vegetables, which research links with a lower risk for vision loss.

Wear sunglasses. Choose a brand that offers protection against both UVA and UVB radiation.

Donate blood. There’s no definitive proof that this strategy works as yet, but if you have iron overload, go ahead and ask your doctor whether you should consider donating blood as a way to reduce your risk for macular degeneration.

Protect your overall health. Don’t smoke, maintain a proper weight, and keep chronic conditions, such as diabetes and high blood pressure, under control.

AMD Warning Signs

Straight lines that look wavy or crooked are an early symptom of wet macular degeneration. If you experience this vision change, promptly schedule an eye exam with your ophthalmologist. There is no conventional cure for macular degeneration, but there are effective stalling treatments that can slow progression of AMD and in some cases even somewhat improve your vision.