Researchers say a healthy lifestyle could lower levels of plaques and tangles that are a hallmark of Alzheimer's disease.
Published in the American Journal of Geriatric Psychiatry, the study found people with mild memory problems who followed a Mediterranean diet, engaged in regular physical activity, or who had a normal body mass index (BMI) were less likely to experience a buildup of beta-amyloid and tau proteins in the brain.
Accumulation of beta-amyloid and tau are hallmarks of Alzheimer's; beta-amyloid clumps together, forming plaques between nerve cells that impair signaling, while tau forms tangles that can damage nerve cells.
The research - led by Dr. David Merrill of the University of California-Los Angeles (UCLA) - comes only days after Medical News Today reported on another study hailing the benefits of a Mediterranean diet against Alzheimer's, providing further evidence that lifestyle factors play an important role in the disease.
However, Dr. Merrill and colleagues say their study is the first to show how such factors affect the buildup of Alzheimer's-related proteins in the brains of individuals with mild memory complaints.
"The fact that we could detect this influence of lifestyle at a molecular level before the beginning of serious memory problems surprised us," says Dr. Merrill.
Lower levels of plaques, tangles with a healthy lifestyle
For their study, the team enrolled 44 adults aged 40-85. Of these, 24 had subjective memory impairment and 20 had mild cognitive impairment (MCI), but none of the participants had been diagnosed with dementia.
Subjective memory impairment is where an individual believes they are having problems with memory, while MCI is where memory problems are observed by the individual experiencing them and other people.
Participants self-reported their BMI, physical activity levels, and the extent to which they followed a Mediterranean diet.
Considered the "heart-healthy" diet, the Mediterranean diet is typically high in plant-based foods - such as fruits, vegetables, and whole grains - and low in red meat. It also involves switching butter for healthy fats - such as olive oil - consuming fish and poultry at least twice weekly, and drinking red wine in moderation.
All study participants underwent a novel type of PET scan known as FDDNP-PET, which measures levels of beta-amyloid plaques and tau tangles in the brain.
The team found that subjects who had a healthy BMI, followed a Mediterranean diet, and who engaged in regular physical activity had lower levels of plaques and tangles in their brains than subjects who did not adhere to such lifestyle factors.
These results, say the authors, highlight the importance of a healthy lifestyle for a healthy brain in later life.
"The study reinforces the importance of living a healthy life to prevent Alzheimer's, even before the development of clinically significant dementia.
This work lends key insight not only into the ability of patients to prevent Alzheimer's disease, but also physicians' ability to detect and image these changes."
Dr. David Merrill