Conference Abstract - AAIC 2026
Authors - Cyrus A. Raji, MD, PhD1, Somayeh Meysami, MD2;3; Rodrigo Solis Pompa, MD4; Saqib Abdullah Basar, MD4; Ahmed Gouda, MSc4; Siavash Khallaghi, PhD4; Saurabh Garg, MSc4; David A. Merrill, MD, PhD1,2; Amar Patel, MD4; Alex Exuzides, PhD, MD4, Daniel J. Durand, MD4; Sam Hashemi, MSc4
1 Washington University in St Louis Mallinckrodt Institute of Radiology, St Louis, MO, USA
2 Pacific Brain Health Center, Pacific Neuroscience Institute and Foundation, Santa Monica, CA, USA
3 Saint John’s Cancer Institute at Providence Saint John’s Health Center, Santa Monica, CA, USA
4 Prenuvo, Vancouver, BC, Canada
5 Prenuvo, Redwood City, CA, USA.
Background: The purpose of this research was to examine associations between dietary habits and MRI-derived measures of brain structure, including regions vulnerable to Alzheimer’s disease (AD) pathology.
Methods: Healthy individuals (n = 3,984) from three sites (mean age 50.63 ± 12.73 years [range: 18-92]; 47.9% women) underwent whole-body 1.5T MRI and completed self-reported dietary questionnaires. Three-dimensional T1-weighted MPRAGE images were used to segment AD-relevant brain regions, including the hippocampus, posterior cingulate gyrus (PCG), and precuneus. Multiple linear regression models assessed associations between dietary habits and regional brain volumes, adjusting for age, sex, body mass index (BMI), and total intracranial volume (TIV).
Results: After adjustment for covariates, higher fruit and vegetable intake was associated with greater hippocampal, precuneus, and PCG volumes. Compared with participants consuming fewer than three portions per day, intake of three to four portions per day was associated with 0.10 mL higher hippocampal volume (95% CI 0.05-0.15; p < 0.001), 0.31 mL higher precuneus volume (95% CI 0.17-0.45; p < 0.001), and 0.06 mL higher PCG volume (95% CI 0.01-0.10; p = 0.020). Intake of more than four portions per day was associated with 0.16 mL higher hippocampal volume (95% CI 0.09-0.22; p < 0.001), 0.58 mL higher precuneus volume (95% CI 0.40-0.77; p < 0.001), and 0.14 mL higher PCG volume (95% CI 0.07-0.20; p < 0.001), relative to fewer than three portions per day. Processed meat consumption was not associated with hippocampal or precuneus volumes; however, consumption of ≥14 servings per week was associated with lower PCG volume (−0.25 mL; 95% CI −0.47 to −0.04; p = 0.020) compared with no processed meat consumption.
Conclusion: Higher fruit and vegetable intake was associated with greater volumes in the hippocampus, precuneus, and PCG, suggesting a neuroprotective association in key AD-relevant regions. In contrast, high processed meat consumption was associated with lower PCG volume, consistent with a pattern potentially indicative of increased subclinical neurodegeneration.
