Macular Degeneration Risk and the Mediterranean Diet

From Medscape - 

The risk for age-related macular degeneration can be cut by more than one-third by eating a Mediterranean-style diet that is heavy in fruit, vegetables, legumes, whole grains, fish, and lean meats, new data from an ongoing Portuguese study suggest.

And these are the first data to conclude that caffeine — not traditionally included in the Mediterranean diet but consumed in beverages popular in the region studied — might be especially protective against age-related macular degeneration, said coauthor Joao Figueira, MD, from the Department of Ophthalmology at the University of Coimbra in Portugal.

The link makes sense, said Dr Figueira, because coffee is high in antioxidants.

Several studies have shown that vitamin A, vitamin C, vitamin E, lutein, antioxidants, and omega-3 help protect against age-related macular degeneration and have health benefits beyond ophthalmology, he reported.

New data from the ongoing Coimbra Eye Study (Ophthalmologica. 2015;233:119-127) were presented during a poster discussion here at the American Academy of Ophthalmology 2016 Annual Meeting.

The analysis involved people 55 years and older who resided in the central region of Portugal — where most people eat a Mediterranean-style diet, heavy on the fruit and vegetables they grow — from 2013 to 2015. Of the 883 people in the cohort, 449 had early-stage macular degeneration with no vision loss and 434 had no macular degeneration.

The researchers wanted to determine whether the diet eaten in that rural region of Portugal had a protective effect against age-related macular degeneration, Dr Figueira told Medscape Medical News.

Diets were assessed with validated food questionnaires that asked about age, sex, height, weight, education, physical activity, smoking habits, and food consumption over the previous year. A score of 9 indicated a Mediterranean-style diet, whereas a score of 0 indicated a completely different diet.

The risk for macular degeneration was 35% higher in people with a score below 6 than in those with a score of 6 or higher (50% vs 39%).

The consumption of fruit was significantly higher in the group without macular degeneration than in the group with macular degeneration (54.5% vs 45.5%; P =.029).

The researchers used software to calculate nutrients in the food and drinks consumed each day and by each patient.

For people who ate the equivalent of one apple each day, there was a 15% decrease in the risk for age-related macular degeneration; for those who ate the equivalent of two apples each day, there was a 20% decrease.

In addition, macular degeneration was less common in people who consumed the equivalent of one shot of espresso each day than in people who did not (45.1% vs 54.4%).

Other than diet, supplements are the only choice for protection against age-related macular degeneration. However, supplements are expensive, adherence is a challenge, and formulations don't match the doses recommended in clinical trials; some are too high and some are too low.

Given these findings, ophthalmologists should consider recommending a Mediterranean-style diet to their patients, Dr Figueira said.

The Mediterranean diet fits with other dietary recommendations, such as promoting kale for patients with age-related macular degeneration, said Elad Moisseiev, MD, a vitreoretinal surgeon at the Tel Aviv Medical Center in Israel.

This is "a good study," he told Medscape Medical News, because "patients were not forced to eat that diet. The researchers are just looking at what they were already eating."

The diet has a place in the "general recommendations you give to patients, along with lifestyle recommendations," he added.

The next step in this study is to rescreen patients to see if those who did not have macular degeneration developed it, and to look at the diet those patients were eating, Dr Figueira reported.

The study was sponsored by the Association for Innovation and Biomedical Research on Light and Image, and supported by Novartis. Dr Figueira reports being a member of the advisory board for Alimera, Allergan, Alcon, Bayer, and Novartis. Dr Moisseiev has disclosed no relevant financial relationships.

American Academy of Ophthalmology (AAO) 2016 Annual Meeting:Poster PO278. Presented October 16, 2016.