Study Suggests Fiber and Micronutrients May Support Brain Health in Older Adults

The study, led by assistant professor Samitinjaya Dhakal, examined the dietary habits and cognitive functions of 72 adults aged 65 and older in the Brookings area. Dhakal stated, "The increasing burden of cognitive diseases represents a major public health challenge that is driven mainly by an aging population and limited prevention options. Existing evidence suggests that modifiable lifestyle factors, including diet, may offer a significant opportunity to prevent or delay cognitive decline."

The findings linked high-fiber diets, healthy unsaturated fats, and micronutrients like Vitamins A and E, magnesium, and potassium to improved brain health and memory. Additionally, carotenoids, compounds that give vibrant colors to fruits and vegetables, were associated with enhanced cognitive function.

However, the study also highlighted a concerning trend: nearly all participants reported inadequate nutrient intake, lacking several vitamins, calcium, potassium, and dietary fiber. It was observed that refined grains, commonly found in white bread and certain cereals, had a negative correlation with cognitive function.

Dhakal remarked, "Our findings suggest that fiber, unsaturated fats, carotenoids, and key micronutrients play a significant role in supporting healthy brain aging, while an over-reliance on refined grains may be at odds with cognitive health. These findings underscore the urgent need for targeted dietary interventions to bridge the nutrient gap in older populations."

Although the study's exploratory nature and modest sample size limit its scope, the results align with established knowledge about how specific nutrients can impact brain health through biochemical processes. For example, fiber fermentation into short-chain fatty acids is known to promote neuronal growth and reduce inflammation, a key factor in cognitive decline.

Dhakal emphasized the existence of a significant 'nutrition gap' even in relatively healthy communities, stating, "Identifying these modifiable dietary factors is only the first step; developing targeted counseling and interventions is crucial for helping older adults meet recommended nutritional guidelines."

Looking forward, Dhakal noted the need for future longitudinal and interventional studies to further explore whether specific dietary changes can effectively slow cognitive decline and enhance brain resilience. Nirajan Ghimire and Sophia Bass, students and research assistants in Dhakal's lab, contributed to the study, which was funded by SDSU's College of Education and Human Sciences Piot Study Funding Program.