Hidden drivers of brain inflammation and how to limit their impact
By Austin Perlmutter, MD
You’ve probably heard a lot about inflammation and why it’s so important that we take steps to reduce the effects of chronic inflammation on our bodies. But now, we’re learning that inflammation in the brain may be one of the most important determinants of our risk for cognitive issues, mental health issues and problems like brain fog and low energy. We certainly want to take steps to decrease unhealthy brain inflammation. Here are 4 hidden contributors to brain inflammation we should all know about:
1. Air pollution
Research published in the last few years has revealed a frightening conclusion: air pollution, even at levels far lower than expected, is linked to much higher rates of mental health issues, dementia, stroke, and even violence. How? Research suggests the answer has to do with brain inflammation. Studies conducted on humans and animals show that air pollution exposure is linked to activation of the brain’s resident immune cells, as well as higher levels of inflammatory markers.
Air pollution can come at us from a range of sources, but some of the most pernicious are hidden in plain sight. These include air fresheners (sprays, diffusers and the scented dangly pine trees on the rearview mirror), unventilated stovetops, scented candles, and industrial chemicals (gasoline fumes, paint thinner, paint). Ways to mitigate these risks include opting out of air freshers, taking care to open the windows/use the hood/vents on your stove, and not storing smelly chemicals in your home.
2. Unnecessary stressful media exposure
It’s a great thing to be informed, but the reality is that for far too much of the time, our exposure to the news, social media, radio, newspapers and other sources of media content are mostly making us upset. The news is a well-known source of stress, and chronic stress is believed to amp up brain inflammation.
This doesn’t mean we should avoid the news and other forms of media completely. Rather, we need to be willing to engage in honest conversations with ourselves about whether our consumption in content is actively enriching our lives and leading to beneficial outcomes. If we’re learning things that help us and motivate us to become positive agents of change in our communities and the world, wonderful! But if we’re just getting stressed without doing anything differently, there’s less to be gained.
3. Sedentary behavior
We’ve all heard about the benefits of exercise for general health. As it relates to the brain, one of the most interesting new learnings has to do with brain immunity and inflammation. When we exercise our muscles, they release molecules called “myokines” which enter the bloodstream and can reach the brain. Myokines with names like irisin are believed to have beneficial effects on the brain in part through their anti-inflammatory signaling.
If weight training and aerobic exercise are beneficial to full-body and brain inflammatory balance, what do we know about sedentary behavior? It turns out that while being overweight is linked to higher levels of inflammation, research shows us that anyone who’s sedentary (regardless of weight) is at higher risk for inflammation. And of course, this doesn’t mean you need to run a marathon! Take a walk, go for a swim, or do some lunges—the key is consistent movement.
4. Traumatic brain injuries
Traumatic brain injury (TBI) is an incredibly common issue affecting millions of people around the world. Importantly, it is recognized as a significant risk factor for the development of brain diseases like Alzheimer’s dementia as well as mood issues and problems with focus and attention. One of the mechanisms connecting these dots appears to be brain inflammation.
Research shows that TBI may increase brain inflammation by activating immune cells called glia that reside within our brains, as well as by damaging the blood brain barrier. Common causes of TBI include falls, motor vehicle accidents and sports injuries. Simple steps to help reduce risk for TBI include always wearing a seat belt when in a motor vehicle, using a helmet whenever appropriate, and especially in the elderly, to take steps to prevent falls.