Study Shows Healthy Lifestyle May Combat Cognitive Decline Even with Signs of Dementia in the Brain

Living a healthy lifestyle, including eating a nutritious diet, exercising regularly, consuming minimal alcohol, and adopting other healthy habits, can help maintain sharp brain function as people age, according to doctors.
However, what happens if the brain already displays signs of beta amyloid or tau — two of the hallmark signs of Alzheimer’s and other brain pathologies? Will a healthy lifestyle still be able to protect against cognitive decline?
According to observational research that studied the brains of 586 people during autopsies and compared the findings with up to 24 years of data on their lifestyles, the answer is yes.
“We found that the lifestyle-cognition association was independent of Alzheimer’s disease pathology burden, suggesting that a healthy lifestyle may provide cognitive benefits even for people who have begun to accumulate dementia-related pathologies in their brains,” said lead author Dr. Klodian Dhana, an assistant professor of geriatrics and palliative medicine at the Rush Institute for Healthy Aging in Chicago.
In essence, the study found that the presence of Alzheimer’s or another neurological disorder did not seem to matter, as the lifestyle changes provided brain resilience against common causes of dementia, according to Dr. Richard Isaacson, director of research at the Institute for Neurodegenerative Diseases in Florida, who was not involved in the study.
For the study, autopsies were performed on 586 individuals living in retirement communities, senior housing, and individual residences 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 testing and filled out annual questionnaires on their lifestyles for over two decades before they died.
The individuals in the study were classified as living a low-risk or healthy lifestyle if they scored highly in five different categories: they did not smoke; they engaged in moderate to vigorous exercise for at least 150 minutes a week; they kept their alcohol consumption to about one drink a day for women and two for men; and they regularly stimulated their brain by reading, visiting museums, and playing games like cards, checkers, crosswords, or puzzles. The fifth category measured how well they followed the Mediterranean-DASH Diet Intervention for Neurodegenerative Delay or MIND diet.
The MIND diet, developed by researchers at Rush University in 2015, incorporates elements of the plant-based Mediterranean diet and the Dietary Approaches to Stop Hypertension (DASH) diet, focusing on lowering blood pressure and cholesterol to prevent heart attacks, strokes, and small blood vessel constriction that can lead to dementia.
The study team then compared lifestyle data to various measures of pathology in the brain, including levels of beta-amyloid, tau tangles, and signs of vascular brain damage. Not everyone who has signs of Alzheimer’s or vascular dementia goes on to develop cognitive issues, but many do.
Researchers also measured markers of three other brain diseases, including drug-resistant epilepsy, frontotemporal degeneration, and Lewy body dementia. The research, published in the journal JAMA Neurology, is “one of the first to harness brain pathology” from autopsies to investigate the link between modifiable risk factors and cognitive decline.
For every 1-point increase in the healthy lifestyle score used in the study, there were 0.120 units less beta-amyloid load in the brain and a 0.22 standardized unit higher score in cognitive performance.
The cognitive benefits remained regardless of the existence of any of the five types of neurological conditions. In fact, “a higher healthy lifestyle score was associated with better cognition even after accounting for the combined burden of brain pathologies,” according to professors Yue Leng and Dr. Kristine Yaffe, who wrote an accompanying editorial.
As an observational study, it’s not possible to prove a direct cause and effect, Yaffe and Leng said. However, the study is “an important step” in understanding the ways people can modify their lives to reduce the risk of Alzheimer’s disease and other types of dementia.

Author: OpenAI