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.

Mediterranean diet and cognitive decline over time in an elderly Mediterranean population

“…Among these studies, highly significant inverse associations were obtained in cross-sectional analyses in Chicago [26] and in Puerto Rican Americans in Boston [27], as well as in the longitudinal Nurses' Health Study [28]. Other studies found borderline significant inverse associations overall in the USA [29] and in Sweden [30], or in subgroups of the studied populations in France [31] and Greece [32]. A weak and nonsignificant inverse association emerged when we evaluated MD adherence in relation to a single MMSE performance in our cohort of elderly men and women [33].…”

Mediterranean Diet, Cognitive Function, and Dementia: A Systematic Review of the Evidence

“…There was suggestive evidence that a higher consumption of milk and dairy was associated with a lower MMSE score, but this was found only in men and not in women (32). Furthermore, Titova et al (49) showed that meat consumption was associated with a worse cognitive performance. In the study by Cherbuin and Anstey (35), consumption of fish and vegetables was associated with a greater risk of cognitive impairment.…”

A Human-Based Integrated Framework forAlzheimer’s Disease Research

“…Redefining the strategy by which current and future NIH research budget is allocated is of particular relevance, especially considering the major role played by lifestyle factors, such as nutrition, physical activity, and level of cognitive training in the determination of AD risk [27][28][29][30][35][36][37] as well as the proven efficacy of intervention strategies aimed at preventing dementiarelated symptoms [88][89][90].…”

“…Further studies aiming to identify the genetic susceptibility to AD and the interaction between specific genetic variations and nutrient intake might be invaluable in designing patient-tailored therapies and preventive approaches based on patient genetic makeups. Novel and more powerful in vivo imaging readouts, such as ultra-high-field magnetic resonance imaging (MRI) and positron emission tomography, are currently available to diagnose AD [86,87] and assess the effects of specific nutritional interventions [88][89][90]. Additionally, novel human connectomics (the production and study of connectomes) provides a three-dimensional reconstruction of neuronal networks within the human brain.…”