As we navigate the journey of aging, the quest for maintaining cognitive well-being becomes increasingly paramount. A recent cohort study, the Rush Memory and Aging Project, delves into the intricate relationship between lifestyle choices, cognitive function, and the presence of dementia-related pathologies in the brain. The findings shed light on the profound impact a healthy lifestyle can have on cognitive reserve, providing a potential shield against cognitive decline in older adults.

The study, conducted from 1997 to 2022, observed 754 deceased individuals, combining lifestyle assessments, cognitive testing, and postmortem brain pathology evaluations. The focus was to unravel whether a healthy lifestyle’s association with better cognitive functioning holds true independently of common dementia-related pathologies such as β-amyloid load, phosphorylated tau tangles, and cerebrovascular pathology.

A composite healthy lifestyle score was constructed based on self-reported factors, including noncurrent smoking, regular physical activity, limited alcohol consumption, adherence to the Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND) diet, and engagement in cognitive activities in late life. This score, ranging from 0 to 5, became a key metric in assessing the relationship between lifestyle choices and cognitive health.

The results revealed a compelling link between a higher healthy lifestyle score and better global cognitive functioning proximate to death. Even more intriguing was the robustness of this association, which remained significant after accounting for common dementia-related brain pathologies. In essence, the study suggests that a healthy lifestyle could contribute to cognitive reserve, allowing individuals to maintain cognitive abilities independently of the presence of these neuropathologies.

While dementia-related brain pathologies did not diminish the strength of the lifestyle-cognition association, an interesting observation emerged. A higher lifestyle score was correlated with lower β-amyloid load in the brain, and approximately 11.6% of the lifestyle-cognition association was attributed to this reduction. This highlights a potential mechanistic link between a healthy lifestyle and reduced β-amyloid burden, a hallmark of Alzheimer’s disease.

The study underscored the significance of lifestyle choices in influencing cognitive health as we age. A healthy lifestyle, encompassing factors such as regular exercise, a balanced diet, and cognitive engagement, appears to offer a cognitive reserve that transcends common neuropathologies associated with dementia. As we strive for longevity, embracing a healthy lifestyle may not only enhance the quality of our years but also fortify our cognitive resilience against the challenges of aging.

K Dhana et al. Healthy lifestyle and cognition in older adults with common neuropathologies of dementia. JAMA Neurology (2024). doi:10.1001/jamaneurol.2023.5491