Age-related cognitive decline is a growing concern with implications for overall health and well-being. A recent study delves into the impact of nutrient-rich dietary patterns, specifically the Mediterranean (MED) and the Mediterranean-dietary approaches to stop hypertension intervention for neurodegenerative delay (MIND) diets, on cognitive function in midlife.
Cognitive decline in midlife varies among individuals based on factors such as cardiovascular health and lifestyle behaviors, with a faster decline potentially posing a risk for Alzheimer’s disease. The MED and MIND diets, known for their neuroprotective and cognition-enhancing properties, have been associated with positive effects on gut microbiota and cognitive functions.
In this study, researchers examined the influence of MED and MIND diets on cognitive function and the 10-year change in cognitive performance among cognitively healthy female twins.
Study Overview:
The study utilized data from the UK Adult Twin Registry, including 509 female twins with complete baseline data on diet and cognitive performance between 1998 and 2000. Baseline dietary intake was assessed using a food frequency questionnaire, with diet scores calculated for adherence to MED and MIND diets.
Cognitive performance was evaluated at baseline and after ten years, measuring various functions such as reaction speed, spatial working memory, and episodic memory. Fecal samples collected at the 10-year follow-up were analyzed to assess gut microbiota.
Key Findings:
Baseline Cognitive Performance: While no significant association was found between MED diet scores and cognitive test scores, each 1-point increase in MIND diet scores was linked to faster reaction time and improved visual episodic memory after adjusting for confounding factors.
10-Year Cognitive Performance: Increased adherence to MED or MIND diets was associated with enhanced episodic memory over the 10-year period.
Monozygotic Twin Pairs: The twin with a higher diet score within monozygotic pairs experienced less decline in global cognition, particularly in visuospatial working memory, though not statistically significant.
Gut Microbiota: Adherence to the MIND diet was linked to higher abundance of short-chain fatty acid-producing bacteria and lower abundance of specific bacteria at the 10-year follow-up. This association became non-significant after adjusting for dietary fiber intake.
Neuroprotective Effects: Both MED and MIND diets demonstrated the ability to preserve episodic and visuospatial working memory in midlife, potentially attributed to their high dietary fiber content and impact on gut microbiota.
While acknowledging potential unidentified genetic factors, the study underscores the neuroprotective benefits of MED and MIND diets and calls for future research with extended follow-ups to better understand the long-term impact on cognitive performance in older age.