Table 1.
Studies examining the association between higher adherence to the Mediterranean diet and brain MRI biomarkers in adults without dementia.
| Study Name | Population Characteristics | Duration | Dietary Assessment or Intervention | MD Assessment Tools | Outcomes | Authors | |||
|---|---|---|---|---|---|---|---|---|---|
| Brain Atrophy | CBVD | Connecti-vity | Functional Brain Networks | ||||||
| Cross-Sectional Studies | |||||||||
| NOMAS | n = 966 (59.3% female), ≥55 years old (mean age 72 years old) | FFQ | Trichopoulou MD score | ↓ log WMH volume | Gardener et al., 2012 [31] | ||||
| WHICAP | n = 707 (34% male) ≥65 years old (mean age 80.3 years old) | FFQ | Trichopoulou MD score | ↓ odds of MRI infarcts, N.S. WMH | Scarmeas et al., 2011 [32] | ||||
| n = 674 (67% female), ≥65 years old(mean age 80.1 years old) | FFQ | Trichopoulou MD score | ↑ TBV, GMV, WMV/Cingulate, parietal, temporal, hippocampus volume and Superior frontal CT distinguish low high MD | Gu et al., 2015 [33] | |||||
| MCSA | n = 672 (52.5% male), 70–89 years old (mean age 79.8 years old) | FFQ | Trichopoulou MD score | increased frontal, average lobar, parietal, and occipital lobe CT | Staubo et al., 2017 [29] | ||||
| Lothian Birth | N = 358 (46.9% female), mean age 79.3 years old | FFQ | PCA (i) Mediterranean-style pattern (ii) Processed pattern |
N.S. TBV, GMV, WMV, NAWMV, gFA, | N.S. gMD | Corley et al., 2020 [30] | |||
| PIVUS | n = 194 (93 female), 75 years old | 1 week food diary at 70 years and MRI at 75 years | Trichopoulou MD score | N.S. TBV, WMV, GMV | Titova et al., 2013 [34] | ||||
| Three-City study Bordeaux | n = 146 (58% female), mean age 73 years old | FFQ, 24h diet recall, collected 8.9 years before MRI | Trichopoulou MD score | N.S. GMV, WMV | preserved structural connectivity | Pelletier et al., 2015 [35] | |||
| NYU |
n = 116 (62% female), 30–60 years old (mean age 50 years old) |
FFQ | Trichopoulou MD score | ↑ CT (+PCC, EC) positively associated with brain structure | Mosconi et al., 2018 [36] | ||||
| n = 52 (70% female), 25–72 years old (mean age 52 years old) | - | FFQ | Trichopoulou MD score | ↑ CT OFC, EC and PCC of the left hemisphere | Mosconi et al., 2014 [37] | ||||
| UIC | n = 82 (52% female), mean age 68.8 years old | - | FFQ | MedDietScore (Panagiotakos) | ↑ DG volumes | N.S. WMH | Karstens et al., 2019 [38] | ||
| Observational Longitudinal Studies | |||||||||
| Lothian Birth | n = 323 70 years old at baseline | 10 years (2 MRIs between 3 years) | FFQ | Trichopoulou MD score | ↓ TBV reduction N.S. GMV, CT | Luciano et al., 2017 [39] | |||
| NYU | n = 70 (69% female), 30–60 years old (mean age 49 years old) | 3 years | FFQ | Trichopoulou MD score | N.S. CT | Walters et al., 2018 [40] | |||
| Randomized Clinical Trials | |||||||||
| DIRECT PLUS | n = 224 abdominally obese/dyslipidemic participants (88% male), ≥30 years old (mean age 51 years old) | 18 months | (i) Control: healthy dietary guidelines (ii) MD (iii) Green-MD: MD higher in polyphenols (+800 mg/day through green tea) and lower in red/processed meat Both MD groups consumed 440 mg/d polyphenols through walnuts | ↓ hippocampal occupancy score decline | Kaplan et al., 2022 [28] | ||||
CBVD: cerebrovascular disease, CT: cortical thickness, DG: dentate gyrus, EC: entorhinal cortex, PCC: posterior cingulate cortex, FFQ: food frequency questionnaire, gFA: general factor of fractional anisotropy, g MD: general factor of mean diffusivity, GMV: gray matter volume, MD: Mediterranean diet, MRI: magnetic resonance imaging, MUFA: monounsaturated fatty acids, NAWMV: normal appearing white matter volume, N.S.: not significant, OFC: orbito-frontal cortex, PCA: principal component analysis, PCC: posterior cingulate cortex, SFA: saturated fatty acids, TBV: total brain volume, WMH: white matter hyperintensities, WM: white matter, WMV: white matter volume.