Omega-3 in seafood protects eyes
Washington: A new study has revealed that omega-3 fatty acids in fish and other seafood have eye-protective effects.
Researchers at Wilmer Eye Institute, Johns Hopkins School of Medicine, wanted to know how the risk of age-related macular degeneration (AMD) would be affected in a population of older people who regularly ate fish and seafood.
High concentrations of omega-3s have been found in the eye`s retina, and evidence is mounting that the nutrient may be essential to eye health.
In the advanced AMD group, the macular area of the retina exhibited either neovascularization (abnormal blood vessel growth and bleeding) or a condition called geographic atrophy. Both conditions can result in blindness or severe vision loss.
"Our study corroborates earlier findings that eating omega-3-rich fish and shellfish may protect against advanced AMD,” said Sheila K. West.
"While participants in all groups, including controls, averaged at least one serving of fish or shellfish per week, those who had advanced AMD were significantly less likely to consume high omega-3 fish and seafood," she said.
The study also looked at whether dietary zinc from crab and oyster consumption impacted advanced AMD risk, but no significant relationship was found – probably because the levels of zinc obtained from seafood/fish were low compared to supplement levels, West said.
Another study at University of Miami Miller School of Medicine has shown that a test that measures the functionality of the eye`s retinal nerve cells may be a key to early detection of glaucoma.
The research, led by Mitra Sehi and David Greenfield was based on the knowledge that retinal ganglion cells (RGCs) become dysfunctional as glaucoma progresses and that such changes can be measured using the pattern electroretinogram optimized for glaucoma screening (PERGLA).
PERGLA measures the electrical activity of a patient`s retina as he or she views an alternating pattern of black and white lines.
PERGLA results showed that RGC dysfunction was reversed and IOP was reduced in all patients following surgery. The patients` central visual field tests improved, as well.
Sehi says these results should be interpreted cautiously until confirmed by larger studies. She calls for longitudinal studies to clarify the relationship between reduced IOP and increased RGC response and to further investigate PERGLA assessment of RGC dysfunction as a biomarker for glaucoma.
The study appears in December`s Ophthalmology journal.