Can oily fish help prevent vision loss in older people?
Publication Date:10/06/2008
Eating oily fish and other foods rich in omega 3 fatty acids may help protect against the most common cause of vision loss in older people, says a new study. But more research is needed before we can know for sure.
What do we know already?
About eight in every 100 people over 65 have a condition called age-related macular degeneration, or AMD. It’s caused by damage to the central part of the retina (the lining inside your eye), called the macula. People with AMD start to notice a blurry patch in the centre of their vision. Over time, vision becomes worse, with many people losing the ability to see fine detail. Some people with AMD go blind.
There are treatments that can slow down this vision loss, but doctors have no way of restoring vision already lost. That’s why researchers are interested in finding out whether certain foods can protect against AMD.
Omega 3 fatty acids are important for keeping the body healthy. They are called “essential” fatty acids because our bodies can’t make them. We have to eat foods containing them. They are found in oily fish such as salmon, trout, mackerel and sardines, as well as in some nuts (fresh tuna counts as oily fish, tinned doesn't).
What does the new study say?
The new study found that people whose diet was rich in omega 3 fatty acids were less likely to get AMD. The risk of someone who ate at least two portions of fish a week getting AMD was about a third less than someone who ate less than one portion of fish a month.
Tell me more about the study’s findings
The study was a review of all the research on this topic, to try and get a definite answer about the role of omega 3 fatty acids in AMD. The researchers found nine studies involving nearly 89,000 people, over 3,000 of whom had AMD.
The researchers say that their findings fit with what is known about AMD. One type of omega 3 fatty acid, called docosahexaenoic acid (DHA), is present in high concentrations in the nerve cells in the retina, the part of the eye that gets destroyed in AMD. So not having enough omega 3 fatty acids in the diet could be lead to AMD, while a diet rich in these fatty acids might protect against it.
Where does the study come from?
The study was done by researchers from the University of Melbourne and the Cancer Council of Victoria, both in Australia, and the National University of Singapore. It was published in a journal called Archives of Ophthalmology.
How reliable are the findings?
The new study was done well. But the nine studies that it is based on were not the best type of research. Many of them relied on people being able to remember details of their diet from some time ago, so the results may not be very accurate.
The researchers say that better-quality studies are needed to confirm the link they found.
What does this mean for me?
This study provides some evidence that eating a diet rich in omega 3 fatty acids may help to reduce the risk of AMD. But it’s not conclusive. More research is needed before this type of diet can be recommended as a means of protecting against AMD.
What should I do now?
For the time being we can’t recommend eating more oily fish, or of other foods containing omega 3, in order to protect against AMD. But you can make sure you eat the recommended amount of fish - two portions of fish a week, one of which is oily fish.
We know that certain things increase the risk of AMD. These include smoking, high blood pressure and having relatives with the condition. You can’t change it if AMD runs in your family. But you can try to stop smoking, and make sure your high blood pressure is under control.
If you notice changes in your sight, it’s important to see your doctor. If you are diagnosed with AMD, there are treatments that can help slow down your loss of vision.
From:
Chong EW-T, Kreis AJ, Wong TY, et al. Dietary omega-3 Fatty Acids And Fish Intake in the Primary Prevention of Age-Related Macular Degeneration. A Systematic Review and Meta-analysis. Archives of Ophthalmology 2008;126:826-833.
To learn more see our information on macular degeneration (AMD).
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This information does not replace medical advice. If you are concerned you might have a medical problem please ask your Boots pharmacy team in your local Boots store, or see your doctor.
