Link Between Gut Microbes and Cognitive Decline: The Role of Food Insecurity

A recent study led by researchers at Mount Sinai Health System reveals a significant correlation between gut microbiome composition and the risk of cognitive impairment among adults, emphasizing how biological factors and social determinants, particularly food insecurity, play a crucial role in brain health. Published in the journal *npj Aging*, this groundbreaking research is the first epidemiological study to explore how food insecurity may modify the relationship between gut microbiota and risk of cognitive impairment (RCI).

The study analyzed data from 360 adult participants in the Survey of the Health of Wisconsin, focusing on the interplay between gut health and food access. According to Shoshannah Eggers, an Assistant Professor in the Department of Epidemiology at the University of Iowa College of Public Health and the study's corresponding author, "Food insecurity is consistently linked to adverse health outcomes such as poorer overall health and adverse neurological health outcomes. Understanding how gut health and social conditions interact gives us a fuller picture of what puts people at risk for cognitive decline."

The researchers found that individuals with lower microbial diversity and specific imbalances in gut bacteria were significantly more prone to cognitive decline. The analysis revealed that food insecurity—defined as limited or uncertain access to adequate food—was independently associated with poorer gut health and diminished cognitive performance. Notably, over 12% of U.S. households faced food insecurity at some point in 2022, marking an increase from 10.2% in 2021, as reported by the U.S. Department of Agriculture.

The study identified distinct groups of gut microbes, or microbial cliques, associated with RCI, using an interpretable machine-learning algorithm. Notably, the presence of certain cliques showed stronger associations with RCI depending on the participants' food security status. For example, a clique containing the microbes Eisenbergiella or Eubacterium was more closely associated with RCI in food-insecure individuals, while a different clique, including Ruminococcus torques and Bacteroides, correlated with RCI among food-secure participants.

Vishal Midya, PhD, MStat, Assistant Professor of Environmental Medicine at Mount Sinai and senior author of the study, commented on the implications of the findings: "These findings suggest that food insecurity is not just a socioeconomic issue—it may be a biological one too, influencing brain health via changes to the gut microbiome. Cognitive impairment, including mild cognitive impairment and dementia, is increasing, particularly among older adults, and is primarily driven by an aging population. Future studies investigating why cognitive problems develop in people should consider food insecurity as one possible contributing factor."

The implications of this research extend to public health strategies, suggesting that addressing nutritional access and gut health concurrently could be vital for reducing dementia risk, particularly in vulnerable populations. The study advocates for future interventions that combine dietary support with microbiome-targeted therapies to enhance cognitive health outcomes. According to Eggers, addressing the dual challenges of food insecurity and cognitive decline will be essential in fostering healthier communities and improving overall public health.

This study is a call to action for integrated public health approaches that address both the nutritional needs and the gut health of populations at risk. As the connection between diet, gut microbiome diversity, and cognitive health becomes clearer, policymakers and health professionals must consider these interrelated factors in their efforts to combat cognitive decline and improve health outcomes across the lifespan.

**References:** Eggers, S., et al. (2025). Food insecurity modifies the association between the gut microbiome and the risk of cognitive impairment in adults. *npj Aging*. doi.org/10.1038/s41514-025-00241-0.