Listen to Your Gut: Infections, Inflammation and the Gut-Brain Connection

Ever had a sinking feeling in your stomach when you heard bad news—or butterflies when you were excited? Those “gut feelings” are more than figures of speech. They’re signs of a real, two-way communication system between your brain and your gut. Scientists call it the gut-brain axis, and it plays a major role in both your mood and your memory.

The Reason? When that connection gets out of balance—from infections, gum disease, or an unhealthy gut microbiome—it can trigger inflammation and immune reactions that may harm your brain over time. In this article we will discuss how treating infections early and supporting a healthy gut may help protect memory and thinking.

The good news: by protecting your gut, you’re also protecting your brain. But it's important to remember, this is only one of many modifiable behavioral risk factors for Alzheimer's and dementia. 

If you'd like a personalized plan, daily activities and support to help address all of your most pressing risks, sign up for a 2 week free trial of Mindr. Better brain health starts today. 

How the Gut Talks to the Brain

Your gut isn’t just about digestion—it’s home to nearly 2,000 species of bacteria that play a key role in everything from your immune system to your mood. These microbes send messages to your brain through nerves, hormones, and immune pathways. The healthy ones produce helpful compounds that calm inflammation and keep your brain’s communication lines open. But when harmful bacteria or infections take over, they can trigger inflammation that affects brain health.

When this system gets out of balance—a condition called dysbiosis—it can set off immune responses and inflammation that damage brain cells and raise dementia risk. Scientists now know that this gut-brain axis dysfunction contributes to conditions like Alzheimer’s and Parkinson’s disease.

In short, what happens in your gut doesn’t stay in your gut—it echoes throughout your body, especially in your brain.

When Bugs Bite - Balancing Your Microbiome 

A healthy body is able to support a healthy gut microbiome, but when infections and medications throw the balance off, consequences can be widespread. Your mouth and gut are gateways to your body’s health—and when infection strikes, your brain may feel the effects.

Let’s start with gum disease. It’s one of the most common chronic infections. Bacteria from the mouth can enter the bloodstream and travel to the brain. Research shows that people with gum disease or tooth loss have higher rates of dementia. In fact, one long-term study found a 20% greater risk of dementia among people who lost teeth due to gum disease. Some scientists even believe beta-amyloid—the protein linked to Alzheimer’s—might be produced as a defense against these bacteria.

And it’s not just dental infections. Hospitalizations for infections such as pneumonia or urinary tract infections are linked to a 60–70% higher risk of dementia. Why? Because every infection triggers inflammation—and repeated “hits” of inflammation can lead to long term neuroinflammation and increase dementia risk.

Animal and lab studies back this up: infections can interfere with the brain’s ability to make new cells in the hippocampus, the area critical for memory and learning. Without new brain cells, your ability to think clearly and remember things suffers.

The 2024 Lancet Commission on dementia emphasizes inflammation and blood vessel damage as major contributors to dementia risk. Chronic infections, poor oral health, and metabolic disease all increase inflammation—and the more persistent it becomes, the greater the impact on brain function.

Practical, Brain-Healthy Steps to Protect Yourself from Infection

You don’t have to overhaul your entire lifestyle to protect your gut and your brain. Small, consistent steps can make a big difference.

• Practice good hygiene and keep up with vaccinations:  Simple steps like handwashing, dental care, safe food handling, and staying up to date on vaccines (flu, pneumococcal, shingles when recommended) help prevent infections that trigger inflammation.

• Feed the good bugs:  Eat plenty of fiber-rich foods—vegetables, fruits, beans, and whole grains—and enjoy fermented foods like yogurt, kefir, kimchi, and sauerkraut. They support the “good bugs” in your gut that keep inflammation in check. Limit highly processed foods and excess added sugars, which can encourage harmful microbes and cause inflammation.

• Treat infections early: Seek prompt care for infections. Treating ongoing gum disease, repeated urinary tract infections, chronic sinus infections, or lung infections prevents chronic inflammation and protects your brain. Regular dental checkups and treating gum disease are good for more than your smile - they lower a source of chronic inflammation and protect your brain health.

• Stay hydrated and active:  Drink plenty of water and stay physically active to help digestion and maintain regularity. Regular exercise improves blood flow, helps the immune system, and reduces inflammation. As Dr. JoAnn Manson of Harvard Medical School puts it, exercise is “the magic bullet for good health.”

• Talk to your clinician about gut or infection concerns: Chronic digestive issues or repeated antibiotic use can alter your microbiome. Work with your provider on a plan that supports both gut and brain health.

• Consider probiotics and supplements: Some trials suggest certain probiotics or fiber supplements can reduce inflammation or improve cognitive performance in those with cognitive impairment, but research is ongoing and not all supplements are the same. Talk with your clinician before starting supplements - especially if you have other health conditions or take medicines.

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Takeaway - Small Habits, Big Gains

Caring for your gut and preventing infections may seem like small steps, but they’re powerful ones. Most of the steps to minimize infections are things you probably already do (or mean to do). Simple habits like brushing your teeth, treating infections quickly, eating plenty of fiber, staying active, and drinking enough water can all have a big impact on your brain health. 

These doable steps overlap with many of the healthy lifestyle recommendations made by the 2024 Lancet Commission on dementia. There are so many things you can do to feel better now and lower inflammation, support the gut–brain axis, and help keep your memory and thinking stronger as you age.

What’s Next

Science shows that despite our best intentions and most sincere dedication, it’s hard to make meaningful lifestyle changes and even harder to maintain them. Only 1 in every 8 or 9 people successfully complete self-guided health interventions. What makes it easier? Many studies, including the U.S. POINTER trial, a study of lifestyle changes conducted by the Alzheimer’s Association, have shown that coaching support and structured intervention plans give people a statistically significant edge over those who are self-guided. 

With Mindr, you will have access to all of these success boosting tools:

• An easy to follow personalized plan based on your most pressing risk factors

• Daily guidance so you know exactly what to do next

• Frequent assessments so you can see your progress

• A human in the loop to support and encourage you

You wouldn’t still be reading this if having a healthy brain wasn’t important to you. The lifestyle changes that will get you there are within your reach. You have the will, we’ll show you the way - one day at a time. You can do this and we can help.

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