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Visual impairment is a significant component of Alzheimer’s disease. Getty Images/FG Trade
  • In a recent study, a novel form of omega-3 helped restore specific markers of eye health in mice bred with aspects of early-onset Alzheimer’s disease.
  • The mice given the supplements showed a 96 percent improvement in retinal function.
  • Visual decline from Alzheimer’s is a complex process that involves changes in brain function and the structure of the eye.
  • Omega-3 fatty acids are essential to health, but the human body does not produce them naturally.
  • Experts caution that the results of this study are preliminary, and people should not start taking omega-3 supplements based on these findings alone.

Omega-3 fatty acids could help ease visual problems in people with Alzheimer’s disease, according to a study presented at Discover BMB, the annual meeting of the American Society for Biochemistry and Molecular Biology.

This study has yet to be published in a peer-reviewed journal.

The researchers developed a form of the omega-3 fatty acid docosahexaenoic acid (DHA) that can cross into the retina to minimize visual difficulties related to Alzheimer’s disease and other disorders, such as macular degeneration.

The scientists tested their supplement in mice bred to exhibit processes found in early-onset Alzheimer’s disease. The dosage of the supplement is equivalent to about 250 to 500 mg of omega-3 fatty acids per day in humans.

After six months, the mice given the supplements showed a 96 percent improvement in retinal DHA content and preserved retinal structure and function.

In healthy eyes, DHA is concentrated in the retina. It helps maintain photoreceptors, cells that convert light into signals sent to the brain.

The results suggest that this supplement could help prevent visual difficulties in humans with Alzheimer’s and other disorders with common DHA deficiency and vision impairment.

One problem with current supplements is that the DHA must be absorbed into the intestine and then into the bloodstream before crossing into the retina. Increasing the DHA in the retina has not been possible until now. The new supplement overcomes both intestinal and blood-retinal barriers.

Further studies are needed to confirm that the DHA supplement is safe and effective in humans.

“Looking into nutritional supplementation to slow the progression of diseases is always a fascinating topic,” says Benjamin Bert, MD, an ophthalmologist at MemorialCare Orange Coast Medical Center in Fountain Valley, CA. “In this case, the researchers are evaluating a different preparation of DHA, LPC-DHA, which they hypothesize will be more usable by the body than currently available DHA formulations. This study is one of the first to use this supplement, so we still have much to learn.”

“Visual impairment is a significant component of Alzheimer’s disease, but while there are indeed degenerative retinal changes in association with Alzheimer’s disease, most of the visual impairment is secondary to brain dysfunction rather than retinal dysfunction,” said Howard R. Krauss, MD, surgical neuro-ophthalmologist and director of Pacific Neuroscience Institute’s Eye, Ear & Skull Base Center at Providence Saint John’s Health Center in Santa Monica, CA.

“Nonetheless, one may think of the retina as both an extension of the brain and a window into the brain,” Krauss continued. “So therapeutic interventions which may demonstrate benefit to retinal health may also benefit brain health.”

Vision problems in people with Alzheimer’s disease can be due to the brain not processing the information sent to it by the eyes, according to the Alzheimer’s Foundation of America. Some problems the person might have include:

“In Alzheimer’s, we know that the structure of the retina gradually changes, and certain layers get thinner,” Bert told Healthline. “The hope is that this process will slow or stop completely with a supplement like the one reported here.”

Omega-3 fatty acids are essential to your health. However, your body does not produce them. Therefore, you must get them from your diet.

Common foods high in omega-3 fatty acids include:

  • Fatty fish, such as salmon, tuna, mackerel, and sardines
  • Fish oil
  • Flax seeds
  • Chia seeds
  • Soybean oil
  • Walnuts

Some foods are fortified with omega-3 fatty acids.

People who do not routinely eat these foods can take supplements, such as fish oil or algal oil.

Omega-3 fatty acids are important parts of cell membranes in your body, according to the National Institutes of Health. Docosahexaenoic acid (DHA) is one of the primary forms of omega-3 fatty acids. DHA levels in your retina are typically high.

Studies with mice are an integral part of the scientific process. Still, they sometimes indicate whether a therapeutic method is safe and effective in humans. The current study is preliminary.

According to Krauss, the “takeaways” from this study indicate that more research is required on the topic and people should not start taking omega-3 supplements based on this study.

While omega-3 and other supplements may benefit some people, over-the-counter supplements vary in purity and concentration. Some supplements, especially in excess, could carry a risk for some people. Anyone considering taking supplements should discuss their use with their primary care provider.”