By: Agata Blaszczak-Boxe
Published: May 11, 2015 01:48pm ET on LiveScience.
Eating a Mediterranean diet that is rich in nuts and olive oil may help delay cognitive decline in older adults, according to a new study.
In the study, researchers randomly chose about 300 people to follow a Mediterranean diet for four years, and asked 145 people to eat a low-fat diet for the same period. Following a Mediterranean diet means consuming many vegetables and fruits, and eating some seafood, while eating only a little meat and dairy.
In the study, 155 of the people who were on a Mediterranean diet were asked to include one liter of extra virgin olive oil in their diet per week, and 147 people were asked to supplement their diet with 30 grams per day of a mix of walnuts, hazelnuts and almonds.
After four years, researchers compared the cognitive function of the people in each group. The average age of the people in the study was 67.
It turned out that the groups of people who followed the Mediterranean diet experienced an improvement in cognitive function over four years, whereas it declined in the people eating the low-fat diet. [6 Foods That Are Good For Your Brain]
"Our results suggest that in an older population, a Mediterranean diet supplemented with olive oil or nuts may counteract age-related cognitive decline," the researchers wrote in the study.
Given the lack of effective treatments for people suffering from a decline in cognitive function and dementia, strategies that could delay the onset of these conditions or minimize their effects are needed, they wrote. Although the new results are encouraging, more research is needed to confirm them, the researchers noted.
The researchers also found that the people in the group who followed the Mediterranean diet plus extra nuts experienced significant improvements in memory abilities, compared with those on the low-fat diet. And those who followed the Mediterranean diet with the extra virgin olive oil showed significantly greater improvement in a number of cognitive functions related to working memory, reasoning and attention, compared with the low-fat diet group.
There are a number of mechanisms that may explain the beneficial effect that the Mediterranean diet and the supplementary foods had on cognitive function, the researchers said. For example, it may be that the so-called phenolic compounds, found in both nuts and olive oil, may help counteract the chemical processes in the brain that lead to neurodegeneration.
Dr. Raphael Kellman, an internist in New York City who was not involved in the study, said that the study shows that, when they are consumed, the omega fats in olive oil and nuts play an important role in improving the condition of cell membranes, including those in the brain.
"When you consume an abundance of these types of oils and fats, then you are improving brain function," which could help prevent neurodegenerative disorders, said Kellman, who also wrote the book "The Microbiome Diet" (Da Capo Press, 2014).
On the other hand, if a person reduces how much of these types of fats they eat, it may have a negative effect on the brain and overall health, he said.
The study also shows that "you need fat — but the issue is what type of fat — not all fat was created equal," Kellman told Live Science. For example, consuming too much saturated fat could affect cell membranes in a negative way, he said.
"So it is about balance," he said.
The study was published today (May 11) in the journal JAMA Internal Medicine.
Follow Live Science @livescience, Facebook & Google+. Original article on Live Science.
Copyright 2015 LiveScience, a Purch company. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.
Our 2024 Coverage Needs You
It's Another Trump-Biden Showdown — And We Need Your Help
The Future Of Democracy Is At Stake
Our 2024 Coverage Needs You
Your Loyalty Means The World To Us
As Americans head to the polls in 2024, the very future of our country is at stake. At HuffPost, we believe that a free press is critical to creating well-informed voters. That's why our journalism is free for everyone, even though other newsrooms retreat behind expensive paywalls.
Our journalists will continue to cover the twists and turns during this historic presidential election. With your help, we'll bring you hard-hitting investigations, well-researched analysis and timely takes you can't find elsewhere. Reporting in this current political climate is a responsibility we do not take lightly, and we thank you for your support.
Contribute as little as $2 to keep our news free for all.
Can't afford to donate? Support HuffPost by creating a free account and log in while you read.
The 2024 election is heating up, and women's rights, health care, voting rights, and the very future of democracy are all at stake. Donald Trump will face Joe Biden in the most consequential vote of our time. And HuffPost will be there, covering every twist and turn. America's future hangs in the balance. Would you consider contributing to support our journalism and keep it free for all during this critical season?
HuffPost believes news should be accessible to everyone, regardless of their ability to pay for it. We rely on readers like you to help fund our work. Any contribution you can make — even as little as $2 — goes directly toward supporting the impactful journalism that we will continue to produce this year. Thank you for being part of our story.
Can't afford to donate? Support HuffPost by creating a free account and log in while you read.
It's official: Donald Trump will face Joe Biden this fall in the presidential election. As we face the most consequential presidential election of our time, HuffPost is committed to bringing you up-to-date, accurate news about the 2024 race. While other outlets have retreated behind paywalls, you can trust our news will stay free.
But we can't do it without your help. Reader funding is one of the key ways we support our newsroom. Would you consider making a donation to help fund our news during this critical time? Your contributions are vital to supporting a free press.
Contribute as little as $2 to keep our journalism free and accessible to all.
Can't afford to donate? Support HuffPost by creating a free account and log in while you read.
As Americans head to the polls in 2024, the very future of our country is at stake. At HuffPost, we believe that a free press is critical to creating well-informed voters. That's why our journalism is free for everyone, even though other newsrooms retreat behind expensive paywalls.
Our journalists will continue to cover the twists and turns during this historic presidential election. With your help, we'll bring you hard-hitting investigations, well-researched analysis and timely takes you can't find elsewhere. Reporting in this current political climate is a responsibility we do not take lightly, and we thank you for your support.
Contribute as little as $2 to keep our news free for all.
Can't afford to donate? Support HuffPost by creating a free account and log in while you read.
Dear HuffPost Reader
Thank you for your past contribution to HuffPost. We are sincerely grateful for readers like you who help us ensure that we can keep our journalism free for everyone.
The stakes are high this year, and our 2024 coverage could use continued support. Would you consider becoming a regular HuffPost contributor?
Dear HuffPost Reader
Thank you for your past contribution to HuffPost. We are sincerely grateful for readers like you who help us ensure that we can keep our journalism free for everyone.
The stakes are high this year, and our 2024 coverage could use continued support. If circumstances have changed since you last contributed, we hope you'll consider contributing to HuffPost once more.
Support HuffPostAlready contributed? Log in to hide these messages.