An inside look at our body’s brain-gut connection.
“Everything is connected.” When it comes to your brain and gut, truer words have never been spoken. If you’ve ever felt butterflies in your stomach before a presentation or raided the cookie jar after a stressful day, you’ve experienced their unique bond.
Known as the “gut brain axis,” the link is so strong that it’s common to feel emotions like fear and sadness at our core. Conversely, our eating habits can cause changes to our mood, energy level and mental and physical health.
We asked Providence registered dietitians Renee McKenna and Whitney Greene to get to the bottom of the issue. Here, they share the basics, including tips to grow a gut microbiome that can help fight anxiety, depression and other health issues.
What is gut health?
Gut health refers to your digestive system and the health of the microorganisms (bacteria, fungi, yeast and viruses) living in your gastrointestinal (GI) track, which runs the entire length of your body.
Each of us has a unique microbiome shaped by everything we’ve consumed throughout our lives.
“Optimally, you want a diverse profile with a nice variety [of microbes],” McKenna said. “Throughout your lifetime, there are things you can do to find a balance.”
What does a balanced gut portfolio look like? It’s comprised mostly of good bacteria, but bad bacteria serve an important purpose as well: strengthening the immune system. Instead of eliminating bad bacteria, you should try to create a harmonious environment.
When your gut is off balance, you might experience bloating, excessive gas, constipation, irregular bowel movements or diarrhea. These are red flags telling you to add more gut-friendly food to your diet. But even if your digestion is textbook, don’t get lax on what you’re eating.
“The reason for incorporating good foods is not just to eliminate GI symptoms, but also to prevent chronic diseases [and mental health issues] that are directly related to our gut and the brain-body connection. It’s two-fold,” McKenna said.
The brain-gut connection
Our emotions and digestive system are interconnected because of tiny neurons hidden in the GI tract. Called the enteric nervous system, it communicates with the central nervous system, which consists of the brain and spinal cord.
Microorganisms in the gut can send signals to the central nervous system that trigger mood changes. The gut is actually one of the primary places that produces and activates serotonin, also known as “the happy hormone.” When your gut is healthy, it can communicate back and forth with your brain to better manage stress and anxiety.
“A high-functioning gut means that when you feel nervous or stressed, your body can call to the brain for more ‘feel-good’ hormones to come to the rescue,” explained McKenna.
Meanwhile, an off-balance gut microbiome, along with inflammation, has been linked to causing several mental illnesses, including anxiety and depression.
Nature’s medicine: Probiotics and Prebiotics
Just like a garden needs nutrient-packed soil to flourish, our gut requires a diverse microbiome to thrive. Take this three-pronged approach to your daily diet:
- Avoid inflammatory foods: Limit the inflammatory foods and beverages you consume for pleasure, like alcohol, animal proteins and fried foods, which can lower the diversity of gut flora.
“They typically fry foods that are already inflammatory because they are high in starch,” Greene said. “The oil they use is high in Omega 6 fatty acids which are a pro-inflammatory type of fat.”
According to Greene, inflammatory foods damage the tiny brushes that coat the lining of the intestines that are responsible for pulling nutrients into the body.
“When we have systemic inflammation that is prolonged, that opens the door for a lot of other health issues. It can lead to a lot of different types of cancers because it's causing damage to cells over time that will not be able to heal themselves,” said Greene, adding that you should fill your plate with anti-inflammatory fruits and vegetables such as berries and spinach.
- Eat probiotics: Probiotics give your body the healthy gut bacteria it needs. Fermented foods (kimchi, kefir, sauerkraut, chia seeds, flax and yogurts) are all an excellent source of probiotics.
Pro tip: While whole foods are preferred, a supplement is a good way to incorporate new and various bacteria if you can’t stomach certain foods or are prescribed antibiotics. McKenna recommends mixing up foods or supplements every two weeks to expose yourself to new strains. Also, if you’re prescribed antibiotics, take a supplement.
- Incorporate prebiotics: You can multiply the impact of probiotics by adding prebiotics to your diet. Studies have found they can reduce cortisol (the stress hormone) so stock up on insoluble fibers like leafy greens that are hard to digest, apple peels, mushrooms, garlic, flax seed, chickpeas, asparagus and onions.
“Prebiotics are the food the good bacteria eat. If you feed the good bacteria, they will create trillions of different bacteria in our bodies,” McKenna said.
“Just remember to hydrate well when upping your fiber intake,” added Greene.
Make an appointment with one of our expert gastroenterologists or mental health counselors.
