Living a healthy lifestyle with an emphasis on a nutritious diet, regular exercise, minimal alcohol consumption and other healthy habits can help keep your brain sharp into old age, doctors say.
But what if your brain already has signs of beta amyloid or tau – two of the hallmarks of Alzheimer’s and other brain diseases? Does a healthy lifestyle still protect you from cognitive decline?
The answer is yes, according to observational research that examined the brains of 586 people during autopsies and compared the findings with up to 24 years of lifestyle data.
“We found that the lifestyle-cognition association was independent of the burden of Alzheimer’s disease pathology, suggesting that a (healthy) lifestyle can provide cognitive benefits even in individuals who have begun to accumulate dementia-related pathology in their brain,” said lead author Dr. Klodian Dhana, assistant professor of geriatrics and palliative medicine at the Rush Institute for Healthy Aging in Chicago, via email.
In other words, the study found that the presence of Alzheimer’s or another neurological disorder “didn’t seem to matter — lifestyle changes made the brain resilient against some of the more common causes of dementia,” said Dr. Richard Isaacson, director of research. at the Florida Institute of Neurodegenerative Diseases.
“It’s like a video game where you shoot monsters,” said Isaacson, who was not involved in the study. “The weapon – lifestyle changes – was able to defeat ghosts, ghouls, ghouls, vampires and zombies.”
For the study, autopsies were performed on 586 people living in retirement communities, nursing homes and single-family homes in the Chicago area who had participated in the Rush Memory and Aging Project between 1997 and 2022. The participants, who lived to an average age of 91 , underwent regular cognitive and physical tests and completed annual lifestyle questionnaires for over two decades before they died.
Study participants were categorized as having a low-risk or healthy lifestyle if they scored high in five different categories: did not smoke; They did moderate to vigorous exercise for at least 150 minutes per week. They kept alcohol consumption at about one drink a day for women and two for men. and they regularly stimulated their brains by reading, visiting museums and playing games such as cards, checkers, crosswords or puzzles.
The fifth category measured how well they followed the Mediterranean Diet-DASH Intervention for Neurodegenerative Delay or MIND diet. Developed in 2015 by researchers at Rush University in Chicago, the MIND diet incorporates much of the plant-based Mediterranean diet, which focuses on fruits, vegetables, whole grains, beans, seeds, nuts and lots of extra virgin olive oil. Red meat and sweets are rarely eaten, but fish, which is packed with beneficial omega-3 fatty acids, is a staple.
The MIND diet also incorporates elements of the Dietary Approaches to Stop Hypertension (or DASH) diet. The DASH diet focuses on lowering blood pressure and cholesterol, which can lead to heart attacks, strokes, and narrowing of the small blood vessels that can lead to dementia. The standard DASH diet limits salt to 2,300 milligrams per day, less than a teaspoon of table salt.
Kobus Louw/E+/Getty Images
Eating a plant-based, low-salt diet is good for the brain, experts say.
The study team then compared the lifestyle data with various measures of brain pathology, including levels of beta-amyloid, tau tangles and signs of cerebrovascular damage, or injury to the brain’s small blood vessels caused by high blood pressure. heart diseases and diabetes.
Not everyone with signs of Alzheimer’s or vascular dementia develops cognitive problems, but many do.
The researchers also measured indices of three other brain diseases, including drug-resistant epilepsy, frontotemporal degeneration, and Lewy body dementia, a neurological disorder that can cause problems with behavior, mood, movement, and cognition.
The research, published Monday in the journal JAMA Neurology, “is one of the first to utilize brain pathology” from autopsies to investigate the relationship between modifiable risk factors and cognitive decline, wrote Professor Yue Leng and Dr. Kristine Yaffe in accompanying article.
Yaffe, who was not involved in the study, is a professor of psychiatry, neurology and epidemiology at the University of California, San Francisco Weill Institute for Neurosciences. Leng, who was also not involved in the study, is an associate professor of psychiatry at the same institution.
For every 1-point increase in the healthy lifestyle score used in the study, there was 0.120 unit less beta-amyloid burden in the brain and 0.22 standard unit higher score in cognitive performance, as measured by a roughly 30-item test that examined attention, memory, language and visuospatial skills.
The cognitive benefits remained independent of the presence of any of the five types of neurological conditions. In fact, “a higher healthy lifestyle score was associated with better cognitive function, even after accounting for the combined burden of brain pathologies,” according to Yaffe and Leng.
More than 88% of a person’s global cognitive score was a “direct correlate of lifestyle,” they said, leaving slightly less than 12% affected by the presence of beta-amyloid.
As an observational study, it is not possible to prove a direct cause and effect, Yaffe and Leng said. However, the study is “an important step” in understanding ways people can modify their lives to reduce their risk of Alzheimer’s disease and other types of dementia.