How exercise helps your gut bacteria

Gut bacteria play an important role in how you feel and think and how well your body fights off disease. New research shows that exercise can give your gut bacteria a boost.

  • Two studies from the University of Illinois show that gut bacteria can be changed by exercise alone.
  • Our understanding of how gut bacteria impacts our overall health is an emerging field, and this research sheds light on the many different ways exercise affects your body.
  • Exercising to improve your gut bacteria will prevent diseases and encourage brain health.

Exercise gets a lot of attention for a lot of little things — like the mere fact that it can make you feel happier, that its good for your muscles and bones, increases your energy levels, benefits your mental health and memory, and lowers the risk of chronic disease — but did you know that exercise also helps your gut bacteria?

What is gut bacteria?

The 100 trillion bacteria in your gut come in 300-500 different varieties. There are nearly two million genes contained within that bacteria. All that bacteria helps regulate your gut. It also has an impact on your metabolism, mood, and the immune system, as well as on illnesses — in particular, type II diabetes, heart disease, inflammatory bowel disease, Crohn's disease, colon cancer, anxiety, depression, autism, and arthritis. The sheer scale of bacteria in the gut is a testament to the gut's complexity. As recently as 2013, a paper in Gastroenterology & Hepatology called the recent awareness of the gut's importance "a new era in medical science."

How exercise helps

You don't have to train as a sprinter to give your gut bacteria a boost, but it won't hurt. Image source: Roman Boed via Flickr

Something new emerges from the world of gut bacteria seemingly every other day. That's why it's worth taking a look at two studies from the University of Illinois that were published near the end of 2017. One study focused on mice; the other study focused on humans. With the mice, the fecal matter from mice who had exercised was transplanted into mice who had and hadn't exercised. The mice who had exercised had a healthier reaction to the fecal matter transplant than the mice who hadn't, demonstrating the beneficial effects of exercise on the gut.

In the human study, 32 obese and lean individuals were tested. They did supervised cardiovascular exercises for 30-60 minutes three times a week for six weeks. Short-chain fatty acids — in particular, butyrate, which promotes healthy intestinal cells, reduces inflammation, and generates energy — increased in the lean participants as a result. Short-chain fatty acids in general are formed when gut bacteria ferment fiber in the colon. In addition to butyrate's specific role, these fatty acids also improve insulin sensitivity and protect the brain from inflammation and neurodegenerative diseases.

Butyrate's role in your gut manifests itself in a variety of ways: if you have Crohn's disease, an increase in butyrate production can strengthen your intestines. It also plays a role in guarding the body against diet-induced obesity.

The study also found that lean individuals produced more butyrate than in obese individuals. Why this happened is still unknown and represents the next question for researchers to explore.

3D printing might save your life one day. It's transforming medicine and health care.

What can 3D printing do for medicine? The "sky is the limit," says Northwell Health researcher Dr. Todd Goldstein.

Northwell Health
Sponsored by Northwell Health
  • Medical professionals are currently using 3D printers to create prosthetics and patient-specific organ models that doctors can use to prepare for surgery.
  • Eventually, scientists hope to print patient-specific organs that can be transplanted safely into the human body.
  • Northwell Health, New York State's largest health care provider, is pioneering 3D printing in medicine in three key ways.
Keep reading Show less

An organism found in dirt may lead to an anxiety vaccine, say scientists

Can dirt help us fight off stress? Groundbreaking new research shows how.

University of Colorado Boulder
Surprising Science
  • New research identifies a bacterium that helps block anxiety.
  • Scientists say this can lead to drugs for first responders and soldiers, preventing PTSD and other mental issues.
  • The finding builds on the hygiene hypothesis, first proposed in 1989.

Are modern societies trying too hard to be clean, at the detriment to public health? Scientists discovered that a microorganism living in dirt can actually be good for us, potentially helping the body to fight off stress. Harnessing its powers can lead to a "stress vaccine".

Researchers at the University of Colorado Boulder found that the fatty 10(Z)-hexadecenoic acid from the soil-residing bacterium Mycobacterium vaccae aids immune cells in blocking pathways that increase inflammation and the ability to combat stress.

The study's senior author and Integrative Physiology Professor Christopher Lowry described this fat as "one of the main ingredients" in the "special sauce" that causes the beneficial effects of the bacterium.

The finding goes hand in hand with the "hygiene hypothesis," initially proposed in 1989 by the British scientist David Strachan. He maintained that our generally sterile modern world prevents children from being exposed to certain microorganisms, resulting in compromised immune systems and greater incidences of asthma and allergies.

Contemporary research fine-tuned the hypothesis, finding that not interacting with so-called "old friends" or helpful microbes in the soil and the environment, rather than the ones that cause illnesses, is what's detrimental. In particular, our mental health could be at stake.

"The idea is that as humans have moved away from farms and an agricultural or hunter-gatherer existence into cities, we have lost contact with organisms that served to regulate our immune system and suppress inappropriate inflammation," explained Lowry. "That has put us at higher risk for inflammatory disease and stress-related psychiatric disorders."

University of Colorado Boulder

Christopher Lowry

This is not the first study on the subject from Lowry, who published previous work showing the connection between being exposed to healthy bacteria and mental health. He found that being raised with animals and dust in a rural environment helps children develop more stress-proof immune systems. Such kids were also likely to be less at risk for mental illnesses than people living in the city without pets.

Lowry's other work also pointed out that the soil-based bacterium Mycobacterium vaccae acts like an antidepressant when injected into rodents. It alters their behavior and has lasting anti-inflammatory effects on the brain, according to the press release from the University of Colorado Boulder. Prolonged inflammation can lead to such stress-related disorders as PTSD.

The new study from Lowry and his team identified why that worked by pinpointing the specific fatty acid responsible. They showed that when the 10(Z)-hexadecenoic acid gets into cells, it works like a lock, attaching itself to the peroxisome proliferator-activated receptor (PPAR). This allows it to block a number of key pathways responsible for inflammation. Pre-treating the cells with the acid (or lipid) made them withstand inflammation better.

Lowry thinks this understanding can lead to creating a "stress vaccine" that can be given to people in high-stress jobs, like first responders or soldiers. The vaccine can prevent the psychological effects of stress.

What's more, this friendly bacterium is not the only potentially helpful organism we can find in soil.

"This is just one strain of one species of one type of bacterium that is found in the soil but there are millions of other strains in soils," said Lowry. "We are just beginning to see the tip of the iceberg in terms of identifying the mechanisms through which they have evolved to keep us healthy. It should inspire awe in all of us."

Check out the study published in the journal Psychopharmacology.

For most of history, humans got smarter. That's now reversing.

We were gaining three IQ points per decade for many, many years. Now, that's going backward. Could this explain some of our choices lately?

The Flynn effect appears to be in retrograde. (Credit: Shutterstock/Big Think)
popular

There's a new study out of Norway that indicates our—well, technically, their—IQs are shrinking, to the tune of about seven IQ points per generation.

Keep reading Show less

Lama Rod Owens – the price of the ticket to freedom

An ordained Lama in a Tibetan Buddhist lineage, Lama Rod grew up a queer, black male within the black Christian church in the American south. Navigating all of these intersecting, evolving identities has led him to a life's work based on compassion for self and others.

Think Again Podcasts
  • "What I'm interested in is deep, systematic change. What I understand now is that real change doesn't happen until change on the inside begins to happen."
  • "Masculinity is not inherently toxic. Patriarchy is toxic. We have to let that energy go so we can stop forcing other people to do emotional labor for us."
Keep reading Show less