An unhappy gut can significantly impact both your mental and emotional health, experts say, affecting your mood and overall well-being.
When your gut is in poor health, you may experience bloating, gas, constipation, abdominal discomfort, mood swings and even acne.
On a recent episode of the 10% Happier podcast, host Dan Harris discussed the connection between gut health and mental health with gastroenterologist and author Dr. Robynne Chutkan.
Harris opened the episode with a brief explanation of the gut-brain axis, which simply put, is a “two-way communication system involving nerves, hormones and immune signals,” he says.
The gut-brain axis links your central nervous system (brain and spinal cord) with your enteric nervous system (the nervous system of the gut). This two-way street allows your brain to influence your gut’s functions—like motility, secretion, and immune responses. In turn, your gut influences your brain’s emotional and cognitive centers.
To kick off their discussion, Chutkan asked Harris to look down at his stomach and consider its position in the body. “It is in the absolute center of your body. It is literally the engine for everything,” she said.
“I would imagine that if your car engine breaks down, even if the brakes are working, or the carburetor is working or something else, you are not going to get very far because your engine is not working. So the gut really fuels the entire body.”
Even if someone eats a healthy, plant-based, and fiber-rich diet — all of which are proven to maintain or improve gut function — if their pH balance is off or the gut lining is damaged, they won’t be able to absorb nutrients properly, Chutkan explained.
“If the gut is not optimized, those nutrients aren’t going to get absorbed and assimilated, and they’re not going to get to the brain and the immune system and all the other parts of the body,” she said.
And that’s why, according to Chutkan, the gut is the No. 1 organ you should focus on: “Everybody in medicine thinks that their field is most important,” she said. “The neurosurgeons think it’s the brain, but it’s the gut.”
An unhealthy gut can impact mood and memory
The enteric nervous system lives within the gut and is often called the second brain, Chutkan said. The system has more nerve cells than a spinal cord, and it allows the gut and the brain to communicate with one another.
“What are they telling each other?” Chutkan asked.
“The brain is controlling things like gut motility, enzyme secretion and also nutrient absorption that we talked about. And the gut is controlling things like mood and memory. When I say controlling, not completely, but influencing dramatically.”
As far back as the 1800s, when melancholia was the term used for what we now know as depression, people were treating it with diet, she said.
In 1859, physician Wooster Beach, suggested that those suffering from melancholia “peruse interesting books, and converse with cheerful friends; and above all, be located amid pleasant scenery, where he can enjoy a water prospect, a country air, and country diet.”
The bacteria in your gut form what’s called the microbiome, and it’s responsible for making certain chemicals in your body function correctly, according to Kaiser Permanente. Those chemicals include neurotransmitters like dopamine and serotonin that affect your mood and sleep, as well as postbiotics that can reduce inflammation and lower stress levels.
When your gut is unhealthy and those chemicals are out of whack, you may experience mood swings, sleep disturbances and brain fog.
Even conditions like Parkinson’s diseases, have connections to gut health. “We know that it begins in the gut,” Chutkan said. “There’s a theory called a gut-first theory of Parkinson’s.”
German neuroanatomist, Dr. Heiko Braak noticed abnormal proteins in the brains of people with Parkinson’s. Those same proteins were present in the gut linings of those individuals years before they developed the brain disease. Braak’s evidence is based on autopsies, but certain research has been done in mice to indicate that injecting those same abnormal proteins into the gut of the animals led to later development of Parkinson’s disease.
“I think that’s one of the clearest connections between the gut and the brain,” Chutkan said.
4 ways to improve your gut health
Now that you know how important it is to keep your gut healthy, you may be wondering how to get your own in better shape.
Dr. Christopher Damman, a gastroenterologist at the Digestive Health Center at the University of Washington Medical Center, shared four ways to improve gut health with CNBC Make It in 2022. Here are his suggestions:
Think about this quote: “Eat food. Mostly plant. Not too much,” from Michael Pollan’s book, ‘In Defense of Food: An Eater’s Manifesto’Give a Mediterranean diet a tryEat whole foods and only use supplements for the nutrients you may be lackingRemember the ‘four phonetic F’s’: fiber, phenols, ferments and good fats
“Shift back to a truly healthy diet which has more balance to it,” Damman said. “The balance that we’ve been missing is whole foods and fiber.”
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