A European study investigated whether eating a Mediterranean-style diet can reduce age-related eye conditions and help prevent blindness.
In Western countries, age-related macular degeneration (AMD) is a leading cause of blindness. AMD is usually found in older people (age-related) and affects the macula — the most sensitive, central part of the retina at the back of the eye. The macula is important for central vision and is essential for daily tasks such as reading, driving, and recognizing faces.
There are two types of AMD: dry and wet. In dry AMD, the more common form, small fatty deposits develop in the macula, which gradually deteriorates. About 10-15% of patients with dry AMD can progress to wet AMD, in which new blood vessels develop underneath the macula. These blood vessels are fragile and may bleed into the retina, which can lead to a rapid deterioration in vision. Currently, there is no treatment for dry AMD, but there are some therapies for wet AMD.
Diet may affect the risk of AMD
Research suggests that the risk of AMD is linked to age, inherited characteristics, and some lifestyle factors such as diet. Understanding the risk factors may help doctors to find ways to reduce the chance of developing AMD and help prevent blindness.
Previous studies have shown that eating a Mediterranean-style diet can lower the risk of conditions such as heart disease and stroke. This diet is rich in vegetables, fruit, legumes, unrefined grains, fish, olive oil, with a moderate intake of wine and low intake of meat.
A research collaboration group in Europe has been investigating whether a Mediterranean-style diet could reduce the risk of developing AMD and help to prevent blindness. They recently published their results in Ophthalmology.
The researchers combined data from two previous large population studies on eye disease and nutrition – the Rotterdam study and the Alienor Study. At the start of the studies, patients had eye examinations and were advised by nutritionists on following a Mediterranean-style diet. The patients were reviewed over a number of years to assess their eye health and adherence to the Mediterranean diet. In the Rotterdam study, patients aged 55 and over were assessed every five years over a 21-year period. In the Alienor study, patients aged 73 and over were assessed every two years over a four-year period.
A Mediterannean diet was associated with a reduced risk of developing AMD
A combined analysis of nearly 5000 patients in the two studies, found that people who had a high adherence to the Mediterranean diet had a 41% reduced risk of developing advanced AMD compared to people who had a low adherence to the diet. There was no individual component of the Mediterannean diet – fish, fruit or vegetables – that was the main contributor to the reduced risk, but rather the combined pattern of the diet reduced AMD risk.
This study supported the idea that a Mediterranean-style diet could reduce the risk of AMD and help to prevent blindness. The research team suggested that, just as people are advised to quit smoking, they should also be encouraged to quit poor diets in order to avoid chronic diseases such as AMD.
Written by Julie McShane, Medical Writer
References:
- Merle BMJ, Colijn JM, Cougnard-Gregoire A, et al. (for The Eye Risk Consortium) Mediterranean diet and incidence of advanced age-related macular degeneration. Ophthalmology (article in press) – doi:10.1016/j.ophtha.2018.08.006
- American Academy of Ophthalmology. New study confirms Mediterranean diet prevents a leading cause of blindness. 30th Sept 2018. https://www.eurekalert.org/pub_releases/2018-09/aaoo-nsc093018.php
