Aged-related macular degeneration is the leading cause of vision loss for adults over the age of 50, affecting as many as 15 million people.

About 30 percent of Americans over the age 75 have some form of age-related macular degeneration.That number is expected to double, said Dr. Joseph Calderone, of Better Vision New Jersey in Cranford and Westfield.

The macular is the central retina in the eye. It allows a person to read, drive, watch TV. Macular degeneration is when the central vision deteriorates, making it harder to see centrally, said Calderone.

There are two types of aged-related macular degeneration: dry and wet. Wet AMD involves new blood vessel growth behind the macular which leaks and bleeds and causes damage to the rods and cones of the macular. While there is no cure, wet AMD, which is the most uncommon type but the type that can occur suddenly and result in more rapid vision loss, can be treated with anti-VEGF drugs. These drugs make those new leaky blood vessels recede.

Dry AMD is the more common type, accounting for about 90 percent of all cases with AMD. But Calderone said while dry AMD is much slower to develop, allowing people affected with it to maintain their useful central vision for many years, there is no effective treatment for it.

But early diagnosis and preventative care are keys to maintaining vision, added Calderone. The No. 1 thing you should do is quit smoking, he said.

Keep your blood pressure and your cholesterol under control along with your blood sugar if you're diabetic.

Exercise regularly.

Eat dark, green leafy vegetables because they contain a chemical called lutein, which is important in macular metabolism.

Get regular eye exams.

"The sooner you can get it diagnosed, the sooner you can get going on slowing it down or intervening," Calderone said.

While AMD is age-related, it can affect people who are out of shape or have high blood pressure or cholesterol.

For more about AMD, you can check out Dr. Calderone's blog.

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