Once again, a study linked a person's diet with the chances of getting age-related macular degeneration (AMD). Macular degeneration is a leading cause of vision loss in Americans 60 years and older, and it has no cure. The study (conducted at the University of Bordeaux, France) found that people who eat a Mediterranean diet are less likely to develop advanced age-related macular degeneration. The study was presented at a conference (not a medical journal), but it builds on other research with similar findings.
What is the Mediterranean diet? It is a diet rich in fruits, vegetables, whole grains, legumes (beans), nuts, seeds, olive oil, and fish. The diet is a good source of fiber, omega-3 polyunsaturated fatty acids (especially fatty fish such as salmon, mackerel, and sardines), and of vitamin C, vitamin E, lutein, zeaxanthin, zinc, and copper. Lutein and zeaxanthin are carotenoids found in green, yellow and red vegetables.
People who eat a Mediterranean diet are less likely to develop advanced age-related macular degeneration (AMD). That's according to research presented May 1 at ARVO 2018, the annual meeting of the Association for Research in Vision and Ophthalmology, in Honolulu, Hawaii. "Higher adherence to the Mediterranean diet was associated with a 39% reduced risk of developing advanced AMD. These results highlight that eating a healthy diet, such as a Mediterranean-type diet, may help to limit progression to advanced AMD," Dr. Benedicte M. J. Merle of the University of Bordeaux, France, and her colleagues write in their abstract.
Dr. Merle, who presented the study, and her colleagues searched the database of the international research collaboration EYE-RISK Consortium for patients without advanced AMD at baseline. They included 4,446 participants age 55 and above who had taken part in the Rotterdam study of disease risk in older people, and 550 age 73 and above from the ALIENOR study of the relationship between nutrition and eye disease.
The researchers collected participants' dietary information at baseline from food-frequency questionnaires. They also developed the MeDi Score (range 0-9), assigning points based on their consumption of fruits, vegetables, cereals, legumes, fish, meat, dairy products and alcohol, and the ratio of monounsaturated to saturated fats.
Overall, 117 participants from the Rotterdam study and 38 from ALIENOR study developed advanced AMD. After adjusting for age, sex, AMD grade at baseline, total energy intake, body mass index, diabetes status, hypercholesterolemia and hypertension, as well as education, smoking status and supplement use, the researchers found that a higher MeDi score (6-9) was significantly linked with a lower risk for incident advanced AMD.
Participants who ate more than the median quantity of fruits, legumes and fish, with above-median ratio of monounsaturated to saturated fatty acids, and who drank little to moderate quantities of alcohol, were at lower risk for incident advanced AMD. Interactions between the MeDi score and either the CFH Y402H or the ARMS2 gene variants were not statistically significant.
Jessica D. Todd, a clinical instructor and coordinated program director in the department of nutrition at Georgia State University in Atlanta, Georgia, told Reuters Health by email, "Research has shown that diet is a major modifiable risk factor in the development of AMD. Lutein and zeaxanthin - carotenoids found widely in green, yellow and red vegetables - as well as omega-3 polyunsaturated fatty acids, especially fatty fish such as salmon, mackerel, and sardines, are key nutrients that reduce the risk of the development and advancement of AMD."
"The National Eye Institute completed the AREDS2 study that supports the use of a nutritional supplement called AREDS2, which contains vitamin C, vitamin E, lutein, zeaxanthin, zinc, and copper, to reduce the development of advanced AMD," added Todd, who was not involved in the study. "The Mediterranean diet is naturally high in the nutrients that formulate the AREDS2 supplement and reduce the progression of AMD."
According to the World Health Organization, AMD is the third-highest cause of visual impairment worldwide and the main cause of visual impairment in industrialized countries. "AMD is the leading cause of permanent vision impairment among older adults," Ms. Todd noted. "The Centers for Disease Control and Prevention (CDC) predict the number of people with AMD to reach 2.95 million by 2020.