An Eye on Vision Supplements
Remedies Magazine, March 2006
Of all the five senses, we rely on sight the most. Losing vision
is a fearsome concept, and if vision diminishes, quality of life also declines.
Age-related macular degeneration (AMD) is a leading cause of vision loss among
middle-aged and elderly Americans, according to the National Eye Institute, a
division of the National Institutes of Health. AMD affects the macula, an oval
spot near the center of the retina that controls central vision. As of 2004,
1.75 million Americans had AMD, and this figure is expected to double by 2020.
The exact cause of AMD remains unknown, but some clinicians
point to continuous free-radical-caused oxidative stress as one factor. What is
known about AMD is its telltale sign of drusen, yellow deposits* under the
retina, which, when increased in size and number, appear to raise risk of AMD
development. Annual eye checkups can keep "an eye out" for any
movement in that direction.
Antioxidants May Help
The National Eye Institute has implemented its Age-Related Eye
Disease Study, based on previously shown links between certain antioxidants and
eye health, to measure how effective dietary supplements are in curtailing AMD
risk. A placebo-controlled trial involving 3,640 individuals tested zinc alone,
antioxidants alone, and a combination thereof. While both solo supplements were
helpful, the greatest disease risk benefit was achieved through the
combination of 500 mg vitamin C, 400 IU vitamin E, 15 mg beta carotene, and 80
mg zinc plus 2 mg copper (the last supplement offsets potential copper
deficiency when taking high doses of zinc). The effect was most profound for
those with intermediate AMD and with advanced AMD in one eye.
The Colors of Vision
Found in ocular tissue, the orange-yellow carotenoids lutein and
zeaxanthin have been associated with curtailing AMD development and progression.
The human body does not manufacture these carotenoids on its own but derives and
distributes them from the diet. In the eye, lutein and its close relative
zeaxanthin are strong singlet oxygen (free-radical) scavengers. One study that
looked at circulating levels of lutein and zeaxanthin had dramatically lower
risk for AMD, fully one-half and one-third the risk, respectively, of those with
low levels of these beta carotene cousins.
A blue-purple berry** high in antioxidant compounds called
flavonoids, bilberry, has decades of anecdotal evidence behind it supporting
improvements n night vision, and a few studies suggest a positive role in
macular health. In fact, a recent animal study has found that bilberry may have
a potential preventive role in AMD.
Clearly, specific antioxidants are helpful for long-term eye
health and possible improvements in visual acuity. These supplements may also
decrease the risk of developing age-related macular degeneration.
*Rose's note: liver, bile
**RN: elderberry
Natural Health Hut
