There is a warning sign in the brain for those suffering from Alzheimer's disease. As a sign of the future, neurofibrillary knots and amyloid plaques can be seen.
Recent research shows that brain changes are not the only cause of dementia. In fact, diet and lifestyle can have a significant impact on our ability to resist the disease in the future.
The MIND diet, also known as the Mediterranean-DASH diet Intervention For Neurodegenerative Delay (DASH diet) and the Mediterranean diet. Rush University's team of nutritional epidemiologists developed it. A 2015 study had previously shown its potential benefits.
Many researchers and the public have focused their attention on this dietary strategy as a possible Alzheimer's prevention strategy.
Studies after studies have shown that the MIND diet, which includes eating more green vegetables, other veggies, fruits, nuts, olive oils, whole grains, and fish, provides some protection against cognitive decline.
A long-term study by the same Rush University team in Illinois found that participants who followed MIND even moderately had improved cognitive function later in life, regardless of any neurofibrillary tangles or amyloid plaques.
Klodian Dhana, a Rush Medical College geriatric researcher on dementia, said that while some people may have enough plaques or tangles in the brains to warrant a post-mortem diagnosis for Alzheimer's disease. However, they don't develop clinical dementia during their lifetime.
"Some people are able to retain cognitive function even when there is an accumulation of brain pathologies. Our study shows that MIND diets have been associated with cognitive functions that are higher than those related to Alzheimer's disease."
Researchers analyzed data from 569 participants who died in a 1997 long-term study called the Memory and Aging Project. Participants agreed to receive yearly clinical evaluations and an autopsy after their death.
The researchers began giving questionnaires to participants in 2004 about the types of food they eat. For this new study, they used these data to retroactively assign patients a score that indicated how close they were to the MIND diet.
It was found that higher MIND scores were associated with better cognitive functioning before death. This was true even when we adjusted for people who had no cognitive impairment at the time of the research or those who were diagnosed with Alzheimer's post-mortem because they had neurofibrillary knots and amyloid plaques.
This study is not without its limitations. Participants reported the diet, which could be incorrect in general, or even for those with cognitive impairment.
"We investigated this concern by excluding participants from the analysis whose first global cognitive assessment was within the lowest 25% of the sample. The team also calculated the cumulative MIND diet score over follow-up to limit measuring error," they explain in the new paper.
"Another limitation of the study sample is that it is mostly composed of white volunteers who consented to annual evaluations, post-mortem organ donor, and thus limits generalizability."
This is a long-term study that shows this dietary approach is worth further exploration. It's also a good idea to eat more green vegetables and other whole foods.
"The diet appeared to have a protective capability and may contribute to cognitive resilience in elderly people." Dhana says.
"Dietary changes can have an impact on cognitive function and the risk of developing dementia. There are simple lifestyle and diet changes that a person can make to help slow cognitive decline as they age and improve brain health."
The Journal of Alzheimer's Disease published the research.