by A diet rich in seafood, fruits, vegetables, nuts and olive oil may reduce the risk of dementia, according to a new study.
An analysis of data from more than 60,000 older adults revealed that choosing to follow a Mediterranean diet reduced a person’s chance of developing dementia by nearly a quarter, even among those with genes that put them at greater risk, according to the report published in Monday in the medical journal BMC Medicine.
“The main message from this study is that, even for people at higher genetic risk, eating a more Mediterranean diet could reduce the likelihood of developing dementia,” said lead study author Oliver Shannon, lecturer in humans. nutrition and aging at Newcastle University.
Among people whose dietary choices were less similar to the Mediterranean diet, “about 17 out of 1,000 people developed dementia during the study’s roughly nine-year follow-up period,” Shannon said in an email.
In contrast, among people whose dietary choices more closely resembled a Mediterranean diet, “only about 12 out of 1,000 people developed dementia,” he added.
What is the Mediterranean diet?
A Mediterranean diet is full of healthy plant foods such as vegetables, nuts and legumes. It is rich in whole grains, fruits and olive oil and fish.
People in the study also typically ate less red or processed meat, sweets and pastries, and drank fewer sugary drinks, Shannon said.
Previous studies have been mixed about whether a Mediterranean diet can help prevent dementia. In fact, a study published in October that examined the medical records of 28,025 Swedes found that the diet did not protect against dementia. In contrast, another study published in May involving nearly 2,000 older adults found that diets rich in foods associated with inflammation—as opposed to the Mediterranean diet, which appears to be anti-inflammatory—were linked to faster brain aging that seen on MRI. scans and a greater risk of developing dementia.
To take a closer look at the impact of the Mediterranean diet on dementia risk, Shannon and colleagues turned to the UK Biobank, which from 2006 to 2010 recruited men and women aged 4 to 69 from across England, the Scotland and Wales. The prospective study currently has more than half a million participants.
Recruits completed a touchscreen questionnaire, participated in an oral interview, and provided biological samples and measures of physical function. Later, the recruits received scans, were assessed for multiple health outcomes and provided information about their diet, sometimes multiple times during the study. Biobank was able to track participants’ health through linked electronic medical records.
An additional dimension to the new study was the inclusion of genetic information in the form of an Alzheimer’s risk score devised in previous research.
“The risk score was constructed using approximately 250,000 individual genetic variants that have been associated with Alzheimer’s disease, which is the most common form of dementia,” Shannon explained.
For the new study, the researchers focused on 60,298 participants who were in their 60s at the time of recruitment. During an average follow-up of nine years, 882 people developed dementia.
When the researchers compiled their data, they found that people whose food consumption more closely mirrored the Mediterranean diet were 23 percent less likely to develop dementia over the years covered by the study.
The new research adds to growing evidence that diet can affect dementia risk even in people who are at higher risk because of their genes, said Dr. Thomas Wisniewski, professor of neurology, pathology and psychiatry and director of Alzheimer’s Disease. Research Center and the Center for Cognitive Neuroscience at NYU Langone.
“This study with very good numbers and a fairly significant effect size shows that, indeed, it is protective for the brain to eat a Mediterranean diet,” Wisniewski said. “It’s positive news and certainly something that anyone can do relatively easily. So that’s good news.”
Reducing the risk of dementia
Diet “is one of the lifestyle issues I discuss with all my patients,” Wisniewski said. “The other thing we usually discuss with patients is the importance of staying physically and mentally active.”
Other important ways to reduce your risk of dementia include:
These are all interventions that anyone can do to keep their brain healthy and reduce their risk of developing dementia,” Shannon said.
The new study found a nearly one-quarter reduction in dementia risk, Wisniewski said. “That’s a pretty big reduction in risk, doing something that’s not that difficult,” he added.
While it’s not known exactly how the Mediterranean diet might reduce dementia risk, it likely has multiple effects, ranging from lowering antioxidants, helping to fight inflammation and improving the state of the microbiome, Wisniewski said.
Without a good medication to treat dementia, experts have focused on lifestyle factors that may have something to do with risk, said Dr. Emily Rogalski, a cognitive neuroscientist and professor of psychiatry and behavioral sciences at Northwestern University Feinberg School of Medicine. .
At present, it is unclear whether there is a point where it is too late to protect against dementia.
“But giving up and saying it’s too late is probably not the right attitude,” he said.
“We used to think that we were born with all the brain cells we’d ever have, and that the brain wasn’t that plastic or malleable or resilient,” Rogalski said. “We’ve learned over the last two decades that there is room for adaptation and change.”
