How Your Midlife Diet and Waist Size Shape Your Brain’s Future
New research reveals that better eating habits and lower waist-to-hip ratio in middle age are linked to stronger brain connectivity and sharper memory as you get older.
Does your diet and waist size also shape your brain health as you age? This study addresses a growing concern: how what we eat and how we manage weight in midlife affects memory and brain connectivity later in life—specifically, when many worry about cognitive decline or dementia.
Key Points
Aim: To explore how long-term diet quality and waist-to-hip ratio (WHR) in midlife are linked to brain connectivity (hippocampus and white matter) and cognitive function in older age.
Methods:
Participants: 512–664 healthy adults from the Whitehall II Study, with diet and WHR measured repeatedly from midlife (around age 48) to late life (around age 70).
Diet: Assessed using the Alternative Healthy Eating Index–2010 (AHEI-2010) over 11 years.
WHR: Measured 5 times over 21 years.
Brain and Cognitive Tests: MRI brain scans and cognitive assessments at age 70.
Analysis: Used advanced statistical models to track changes and associations over time, adjusting for age, sex, education, physical activity, and other key factors.
Results:
Better Diet Quality: Linked to stronger hippocampal functional connectivity (especially to the occipital lobe and cerebellum), better white matter integrity (higher fractional anisotropy, lower diffusivity), and improved memory and cognition.
Higher WHR: Associated with poorer white matter integrity (higher mean and radial diffusivity, lower fractional anisotropy), especially in regions like the cingulum and longitudinal fasciculus, and worse working memory and executive function.
Mediation: Some negative effects of higher WHR on cognition were explained by changes in white matter connectivity.
