By: Dr Avi Verma

Your Mouth May Influence Your Mind: How Oral Bacteria Could Affect Brain Health

A growing body of research now suggests that the bacteria in your mouth may do more than just influence your dental hygiene—they might also play a significant role in your brain’s health as you age. According to a recent study, certain oral bacteria are linked to better memory and attention, while others may increase the risk of mild cognitive impairment (MCI), a condition often considered a precursor to dementia and Alzheimer’s disease.

What the Research Reveals

In this groundbreaking study conducted by researchers in the UK, scientists examined the oral microbiome—the ecosystem of bacteria living in the mouth—of 115 older adults. Of these, 55 had mild cognitive impairment. The study found that:

 A higher presence of beneficial bacteria like Neisseria was associated with stronger executive function, visual attention, and working memory.

 Conversely, a greater abundance of harmful bacteria such as Porphyromonas was linked to poorer cognitive outcomes and a higher likelihood of being diagnosed with MCI.

 Another bacteria, Prevotella intermedia, was found to be more common in individuals carrying the APOE4 gene, which is known to raise the risk for Alzheimer’s disease.

Why This Matters

As much as 15% of older adults experience MCI, and oral health may be a hidden factor contributing to that decline. Previous studies have already shown a connection between gum disease (periodontitis) and worsened brain function.

Researchers believe the connection may work in two main ways:

1. 1. Pathogenic (harmful) bacteria from the mouth might enter the bloodstream and travel
      to the brain, potentially triggering inflammation.

1. 1. These same harmful bacteria may also disrupt beneficial nitrate-reducing bacteria, reducing the availability of nitric oxide—a molecule essential for brain function and memory processes.
      
      Food for Thought: Diet and Oral Bacteria
      
      

      Interestingly, diet plays a crucial role in shaping the oral microbiome. Nitrate-rich diets, such as the Mediterranean diet or DASH (Dietary Approaches to Stop Hypertension), are known to support beneficial bacteria like Neisseria. These diets include foods like:  Leafy greens (e.g., spinach, arugula)

 Beets
 Carrots
 Celery

By supporting beneficial bacteria, such a diet may help maintain better brain health over time. Looking Ahead While this research is still developing, it opens the door to potential preventive strategies.
Improving oral hygiene, incorporating nitrate-rich foods, and possibly using oral probiotics in the future might all become part of a broader toolkit to help delay cognitive decline or reduce the risk of neurodegenerative diseases like Alzheimer’s.

Disclaimer:

This article is intended for general informational and educational purposes only and does not constitute medical advice. Please consult with your physician or a qualified healthcare professional before making any changes to your diet, oral hygiene, or health routines based on this information.