Total and different types of olive oil consumption, gut microbiota, and cognitive function changes in older adults.

Higher virgin olive oil consumption was associated with improved cognitive function over a 2-year follow-up period.

• Study included 656 participants aged 55 to 75 years (mean age 65.0 ± 4.9y, 47.9% women)
• Participants had overweight/obesity and metabolic syndrome and were cognitively healthy at baseline but at high risk of cognitive decline
• Cognitive function was assessed using a comprehensive battery of neuropsychological tests at baseline and at 2-year follow-up
• Results derived from multivariable linear regression models

Higher virgin olive oil consumption was associated with more diverse gut microbiota overall structure at baseline.

• Association observed in 656 participants who provided stool samples at baseline
• Dietary intake assessed via validated semi-quantitative food frequency questionnaire at baseline
• The association pertained to overall microbiota structure (beta diversity) rather than alpha diversity alone
• Results derived from multivariable linear regression models

Higher consumption of common olive oil was associated with lower alpha diversity of microbial communities and accelerated cognitive decline.

• Common olive oil showed an opposite pattern to virgin olive oil on both gut microbiota alpha diversity and cognitive outcomes
• Lower alpha diversity indicates less diverse microbial communities
• This finding contrasts with the beneficial associations observed for virgin olive oil consumption
• Results derived from multivariable linear regression models in the same cohort of 656 participants

Gut microbiota, particularly the taxon Adlercreutzia, may serve as a mediator in the association between virgin olive oil consumption and positive changes in general cognitive function.

• Mediation analysis was conducted to explore the gut microbiota as an intermediary pathway
• Adlercreutzia was specifically identified as a potential mediator taxon
• The mediation pathway links virgin olive oil consumption to favorable gut microbiota alterations and subsequently to cognitive preservation
• This represents a novel mechanistic insight from human observational data

The study population consisted of older adults with overweight/obesity and metabolic syndrome who were cognitively healthy at baseline but at high risk of cognitive decline.

• 656 participants were included with stool samples and complete dietary and cognitive assessments
• Age range was 55 to 75 years with mean age 65.0 ± 4.9 years
• 47.9% of participants were women
• This was a prospective cohort study design with a 2-year follow-up period

Virgin olive oil and common olive oil differ in their associations with gut microbiota composition and cognitive outcomes, underscoring the importance of olive oil subtype in dietary assessments.

• Virgin olive oil was associated with beneficial effects on both gut microbiota diversity and cognitive function
• Common olive oil was associated with detrimental effects on both alpha diversity and cognitive decline
• Total olive oil consumption was examined alongside its subtypes (virgin olive oil and common olive oil) separately
• The authors note these findings 'underscore the potential of microbiota-targeted dietary strategies to promote cognitive health in aging populations'