title: Mediterranean diet habits in older individuals: associations with cognitive functioning and brain volumes.
abstract: To examine the association between dietary habits, cognitive functioning and brain volumes in older individuals, data from 194 cognitively healthy individuals who participated in the Prospective Investigation of the Vasculature in Uppsala Seniors cohort were used. At age 70, participants kept diaries of their food intake for 1week. These records were used to calculate a Mediterranean diet (MeDi) score (comprising dietary habits traditionally found in Mediterranean countries, e.g. high intake of fruits and low intake of meat), with higher scores indicating more pronounced MeDi-like dietary habits. Five years later, participants' cognitive capabilities were examined by the seven minute screening (7MS) (a cognitive test battery used by clinicians to screen for dementia), and their brain volumes were measured by volumetric magnetic resonance imaging. Multivariate linear regression analyses were constructed to examine the association between the total MeDi score and cognitive functioning and brain volumes. In addition, possible associations between MeDi's eight dietary features and cognitive functioning and brain volumes were investigated. From the eight dietary features included in the MeDi score, pertaining to a low consumption of meat and meat products was linked to a better performance on the 7MS test (P=0.001) and greater total brain volume (i.e. the sum of white and gray matter, P=0.03) when controlling for potential confounders (e.g. BMI) in the analysis. Integrating all dietary features into the total MeDi score explained less variance in cognitive functioning and brain volumes than its single dietary component meat intake. These observational findings suggest that keeping to a low meat intake could prove to be an impact-driven public health policy to support healthy cognitive aging, when confirmed by longitudinal studies. Further, they suggest that the MeDi score is a construct that may mask possible associations of single MeDi features with brain health domains in elderly populations.
authors.affiliation: Department of Neuroscience, Uppsala University, Sweden. Electronic address: olga.titova@neuro.uu.se.
authors.forename: Olga E
authors.initials: OE
authors.lastname: Titova
authors.forename: Erika
authors.initials: E
authors.lastname: Ax
authors.forename: Samantha J
authors.initials: SJ
authors.lastname: Brooks
authors.forename: Per
authors.initials: P
authors.lastname: Sjögren
authors.forename: Tommy
authors.initials: T
authors.lastname: Cederholm
authors.forename: Lena
authors.initials: L
authors.lastname: Kilander
authors.forename: Joel
authors.initials: J
authors.lastname: Kullberg
authors.forename: Elna-Marie
authors.initials: EM
authors.lastname: Larsson
authors.forename: Lars
authors.initials: L
authors.lastname: Johansson
authors.forename: Håkan
authors.initials: H
authors.lastname: Ahlström
authors.forename: Lars
authors.initials: L
authors.lastname: Lind
authors.forename: Helgi B
authors.initials: HB
authors.lastname: Schiöth
authors.forename: Christian
authors.initials: C
authors.lastname: Benedict
mesh_terms: D000367:Age Factors; D000368:Aged; D000375:Aging / Q000523:psychology*; D001921:Brain / Q000033:anatomy & histology*; D003071:Cognition; D038441:Diet, Mediterranean; D005247:Feeding Behavior; D005260:Female; D015577:Geriatric Assessment; D006801:Humans; D016014:Linear Models; D008279:Magnetic Resonance Imaging; D008297:Male; D008460:Meat; D015999:Multivariate Analysis; D009483:Neuropsychological Tests; D009929:Organ Size; D011446:Prospective Studies; D013548:Sweden; D013997:Time Factors
keywords: 7MS; AD; Alzheimer's Disease; Brain morphometry; CI; Cognitive function; Confidence interval; EPN; Elderly; Ethics Committee of Uppsala; FWE; Family Wise Error; MCI; MMSE; MRI; Magnetic resonance imaging; MeDi; Meat intake; Mediterranean diet; Mild cognitive impairment; Mini-mental state examination; PIVUS; Prospective Investigation of the Vasculature in Uppsala Seniors; SEM; SPM; Seven minute screening; Standard error of mean; Statistical parametric mapping; TFE; Turbo Field Echo; VBM; Voxel Based Morphometry