Higher fish and lower meat intake may contribute to brain structure benefits.
What are the effects of eating a Mediterranean-type diet on MRI measured brain volume?
What was done?
674 participants with an average age of 80.1 years were given food frequency questionnaires, identifying which foods they ate most often. MRI scans were taken for each participant examining brain volume and cortical thickness. The degree to which a diet aligned with a Meditarannean diet was examined in relation to individuals’ MRI results.
What was found?
Higher fish intake was associated with significantly larger total gray matter volume and lower meat intake was associated with larger total brain volume.
How does this affect me?
Adopting a Mediterranean-style diet, i.e. high fish, low meat, may protect against brain atrophy in older age.
Objective: To determine whether higher adherence to a Mediterranean-type diet (MeDi) is related with larger MRI-measured brain volume or cortical thickness.
Methods: In this cross-sectional study, high-resolution structural MRI was collected on 674 elderly (mean age 80.1 years) adults without dementia who participated in a community-based, multiethnic cohort. Dietary information was collected via a food frequency questionnaire. Total brain volume (TBV), total gray matter volume (TGMV), total white matter volume (TWMV), mean cortical thickness (mCT), and regional volume or CT were derived from MRI scans using FreeSurfer program. We examined the association of MeDi (scored as 0–9) and individual food groups with brain volume and thickness using regression models adjusted for age, sex, ethnicity, education, body mass index, diabetes, and cognition.
Results: Compared to lower MeDi adherence (0–4), higher adherence (5–9) was associated with 13.11 (p = 0.007), 5.00 (p = 0.05), and 6.41 (p = 0.05) milliliter larger TBV, TGMV, and TWMV, respectively. Higher fish (b = 7.06, p = 0.006) and lower meat (b = 8.42, p = 0.002) intakes were associated with larger TGMV. Lower meat intake was also associated with larger TBV (b = 12.20, p = 0.02). Higher fish intake was associated with 0.019 mm (p = 0.03) larger mCT. Volumes of cingulate cortex, parietal lobe, temporal lobe, and hippocampus and CT of the superior-frontal region were associated with the dietary factors.
Conclusions: Among older adults, MeDi adherence was associated with less brain atrophy, with an effect similar to 5 years of aging. Higher fish and lower meat intake might be the 2 key food elements that contribute to the benefits of MeDi on brain structure.