THURSDAY, December 26, 2019 (HealthDay News) – Diets rich in red meat and fatty foods may help stimulate a leading cause of vision loss in older Americans, recent research suggests.
The study found that people who ate more typical western diets were three times more likely to develop an eye condition that steals their central vision: age-related macular degeneration in late stages.
"What you eat seems to be important to your vision and to know whether or not you have vision loss later in life," said lead author Amy Millen. She is an associate professor in the department of epidemiology and environmental health at the School of Public Health and Health Professions at the University of Buffalo, in Buffalo, New York.
"People know that diet influences cardiovascular risk and obesity risk, but the public may not know that diet can affect vision loss," said Millen.
Age-related macular degeneration occurs when a part of the eye called the macula is damaged. Sometimes this happens when deposits called drusen grow in the macula. Or it can happen when new blood vessels continue to form and drip blood, scarring the macula, according to the American Academy of Ophthalmology.
Genetics and smoking are known risk factors for age-related macular degeneration.
The study included almost 1,300 people from a nationally representative sample. Most had no macular degeneration. There were 117 who had AMD early, and 27 were late.
All study participants completed surveys about their diets twice during the 18-year study.
The researchers classified food into 29 categories to measure the quality of the diet.
They discovered that people who ate a more western diet were much more likely to develop late AMD. Foods linked to a higher risk include:
- Red and processed meats
- Fats, such as margarine and butter.
- High-fat dairy
- Fried food.
"The diet is a way of modifying the risk of vision loss due to age-related macular degeneration," Millen said, especially if he has a family history of the disease.
He noted that since the study was observational, he could not prove that eating healthy foods would reduce the risk of AMD, but said he did show foods that he probably does not want to eat frequently.
Dr. Avnish Deobhakta, an ophthalmologist at the New York eye and ear nurse at Mount Sinai in New York City, was not involved in the study, but said the findings did not surprise him.
"This study shows what we suspect. A diet rich in fatty foods, processed meats and refined grains makes the most severe form of macular degeneration more likely," said Deobhakta.
Both Millen and Deobhakta said that the inflammation caused by a less healthy diet and stress in the eye cells (oxidative stress) are probably behind the increased risk.
"The eyes are a sentry for the rest of the body. In the small blood vessels of the eyes, even small changes that you would not otherwise notice in other organs, you will notice in the eyes," said Deobhakta.
So can you make up for a lifetime by eating badly? It is not known. But both experts said that a healthy diet, full of vegetables (especially dark green and leafy vegetables) and fruits and fatty fish, contains important nutrients for eye health, such as lutein and zeaxanthin.
"It's hard to change the way you eat overnight, but it's almost certainly a decades-old process, so try slowly to move towards more virtuous behavior with food. Try supplementing your current diet with more vegetables from leaf and increase your fish consumption, "said Deobhakta.
And both experts advised not to smoke.
The study was published in the December issue of British Journal of Ophthalmology.