Dietary Supplement Could Help Prevent Blindness

The leading causes of vision loss are related diseases of the retina known as retinopathy. Now, new research explains how a dietary supplement may help to prevent and treat these diseases.

Retinopathy of prematurity affecting infants, diabetic retinopathy in adults and age-related macular degeneration in older people, all involve abnormal blood vessel growth in the retina that interferes with vision.

In this new research, Lois Smith of Harvard Medical School and colleagues detail how omega-3 fatty acids block blood vessel growth in the retina.

They used laboratory mice as a stand-in for human subjects and identified the specific molecules responsible for the beneficial effect. Those molecules are produced when the body breaks down, or metabolizes, the components of the omega-3. The researchers blocked each of those metabolites, one at a time.

"And in doing that," Smith explained, "we then found exactly what the major metabolite was that is protecting the retina during this disease process."

They also found that aspirin and related drugs do not block the beneficial effect. That’s important because many older retinopathy patients regularly take aspirin and other nonsteroidal anti-inflammatory drugs.

Smith says the research may shed some light on other diseases where out-of-control blood vessel growth may play a role.

"The results can be interpreted so that there might be implications for cancer or implications for other disease where blood vessel formation is important, such as rheumatoid arthritis, but we have not done that work in cancer, so we can only suggest that that is an interesting avenue to pursue."

Omega-3 is currently being tested in older patients with age-related macular degeneration, and studies of other retinopathy diseases are planned. If research eventually proves the effectiveness of omega-3 in preventing or treating retinopathy, Smith says the cost savings are potentially enormous.

"The cost of using omega-3 supplements is about $10 a month. The current treatment for age-related macular degeneration costs $4,000 a month. So you can see the difference in health care costs is really huge."

Treating macular degeneration with omega-3 might save almost $50,000 a year. If it’s proved to prevent vision loss in the first place - that’s priceless.