Vitamins and Your Eyes

Research is providing a growing body of evidence that certain vitamins and minerals may reduce your chance of developing cataracts or macular degeneration. Thanks to this new information we have reason to believe that a diet rich in fruits and vegetables along with vitamin supplements may enhance the body’s defenses against cell damage which leads to these kinds of eye disease. Numerous laboratory and clinical studies have shown a link between vitamin and mineral deficiency and cataracts. Likewise, studies have found a reduced risk of cataracts in patients with high dietary intake of vitamins A, C, D, E, Riboflavin, Niacin, Thiamin, Iron and Folic Acid.

Curtailing Cataracts:

The same oxidative process that renders food rancid accounts for the tissue damage associated with cataracts and other diseases. "Free-radicals" are atomic sized particles released from tissue that can damage certain types of molecules. In the eye, it is the large protein molecules located in the lens which are damaged by the release of free radicals. The free radicals can come from a variety of places but ultra-violet radiation from the sun is the most relevant to the eye. Since sunlight can cause the damage that leads to the development of cataracts, protecting the eyes from UV has become an important issue lately. Either good quality sunglasses should be worn, or UV protection should be built into prescription eyeglasses. Even clear glasses can be made to protect the eye from 100% of UV radiation.

The body has a number of natural defenses against free radicals. An enzyme called glutathione can actually search out and destroy free radicals. However, certain vitamins and minerals are necessary for glutathione to work properly, mainly riboflavin and selenium. Vitamins A, C, and E can, by themselves, neutralize free radicals. For the body to absorb these vitamins during digestion, the minerals copper and zinc must be present. Several manufacturers have come out with combinations of vitamins and minerals appropriate for the eye. See the box on the next page for a list of currently available "One a Day" vitamin pills that incorporate these combinations.

Macular Degeneration:

Approximately 75,000 Canadians are legally blind due to degeneration of the central retina (the macula). Many more have less advanced chronic age-related macular degeneration. As with cataracts, long term exposure to Ultra-Violet light is believed to be a contributing factor. People with lightly coloured eyes or those who smoke appear particularly vulnerable. The macula consumes tremendous amounts of oxygen and nutrients, and is among the most metabolically active tissues in the body.

In one study, patients with early macular degeneration who took a vitamin supplement, 88% had either the same or better vision six months later. Of those who did not take a vitamin, only 59% had no loss of vision. Researchers have discovered that the retina has the highest concentration of zinc anywhere in the body. Another study of patients with macular degeneration found 86% of those taking zinc showed no vision loss over a two year period, while those that did not take zinc only 66% showed no visual loss.

Recommendations:

Despite the increasing amount of evidence, many experts still disagree on whether there is a real benefit in taking vitamin supplements for the eye. Some feel that a balanced diet is the best way to obtain the vitamins and minerals needed for all health-care needs. Others maintain that poor digestion in seniors, those most at risk for degenerative eye disease, makes vitamin supplements necessary. Until we see the results of well controlled studies this debate will continue.

Caution: vitamin supplements may not help everyone, and bad reactions can occur if more than one pill is taken per day (for example zinc can be toxic in larger doses).

Our recommendations are for anyone with early signs of cataracts or macular degeneration, to consult with their family doctor, and unless otherwise contra-indicated take a daily multi-vitamin containing at least: