Macular Degeneration

Over a third of referrals to the Royal Blind Society of Australia stem from this eye condition, the most common cause of blindness in those over the age of 50. Getting plenty of antioxidants – potent protectors of the body's cells – appears to be a key factor in preventing this disorder.

What is it?

In macular degeneration, the macula – the light-sensitive area in the centre of the retina that controls the central visual field and the ability to see colours – breaks down and impairs your eyesight. Though your peripheral vision – the ability to see the outside edges of the scene you are looking at – remains intact, the centre of your field of vision is blurry, grey or filled with a large blank spot. As a result, the condition may make it difficult or impossible to read, drive, watch television or even recognise someone's face.

There are two forms of this disorder. In age-related ('dry') macular degeneration, the macula thins and bits of debris gather beneath it. The condition develops slowly and accounts for 90% ofall cases. In haemorrhagic ('wet') macular degeneration, new blood vessels grow underneath the retina, pushing up like tree roots cracking the pavement above. These fragile vessels often leak fluid and blood, causing scar tissue to form and central vision to deteriorate rapidly.

What causes it?

Damage from free radicals, the unstable oxygen molecules that can harm cells, is probably the leading cause of macular degeneration. A diet high in saturated fats, cigarette smoke and exposure to sunlight can lead to the formation of free radicals in the retina. High blood pressure, heart disease and diabetes may also be contributing factors because they limit blood flow to your eyes.

What are the symptoms?

• A blurry, grey or blank spot in the centre of the field of vision; peripheral vision remains sharp in one or both eyes.
• Distorted vision, in which straight lines look wavy, printed words seem blurred or object appear to be the wrong size or shape.
• Faded or washed out colours.

Are there any natural therapies?

Working as antioxidants, vitamin C, vitamin E and different types of carotenoids can neutralise the free radicals linked to macular degeneration. The carotenoids lutein and zeaxanthin are especially important – in fact, the macula's yellow colour is due to their presence. They protect the macula by filtering ou the sun's harmful ultraviolet rays. Zinc plays a key role in the functioning of the retina as well. Many older people are deficient in this mineral and some research suggests that it can slow the progression of the disorder. You may need extra copper if you're taking zinc for longer than a month.

For maximum protection, take all these supplements, plus bilberry. This herb contains antioxidant compounds and enhances blood flow to the retina. Grape seed extract or gingko biloba can be substituted for the bilberry. Though neither is as effective as bilberry, grape seed may be a good choice if you have poor night vision, and ginkgo is useful for those who also show signs of memory loss. The prescription mineral selenium can be added in an effort to boost the body's overall antioxidant activity.

What else can I do?

• Wear sunglasses and a wide-brimmed hat to protect your eyes.
• Stop smoking: it's a major combination to macular degeneration.
• Eat lots of dark green vegetables; they're high in the antioxidants carotenoids lutein and zeaxanthin.

Did you know?

People with blue or green eyes need to take special care, because they are particularly susceptible to the sun damage that can cause macular degeneration.