The brain gut axis regulates a number of processes, including digestion, metabolism, and your mood. Not only was every molecule in your brain once on your fork, but how well your gut functions impacts how well you feel emotionally. Read this post to learn four-and-a-half ways to improve your mental health by improving your gut health.
Every molecule in your brain once was on your fork. Your gut directly impacts your mental health, from nutrient absorption (which impacts the physical building blocks of the brain), to inflammation (which can lead to cytokines to damage your brain), to your microbiome (which impacts your physical and mental health). (1) Your gut health is actually a huge contributing factor to your mental health.
So in this post you’ll learn four-and-a-half ways to improve your gut health, which can improve your mental health.
The Vagus Nerve and the Brain Gut Connection
So real quick, let’s talk about the gut-brain microbiome axis.
The vagus nerve is the longest nerve in the body. It runs from the brain all over the body, from the eyes to the throat, down to the chest and stomach, down into the pelvis. And it sends messages in both directions, from the brain to the gut and from the gut to the brain. (2) And those messages are often about whether to be stressed or to be relaxed.
When the brain is healthy and happy and when you’re surrounded by friends and feeling relaxed, the brain sends messages to the gut to have healthy hunger and fullness cues, to digest and absorb nutrients, and to process food in a healthy way. This is the rest-and-digest state of the autonomic nervous system.
When you’re stressed, on the other hand, the fight-or-flight response essentially puts eating and processing food and pooping on the back burner.
So for example, that huge assignment at work feels like a threat. It triggers the survival mode, and the brain cues the digestive system to decrease hunger or, on the other hand, to hurriedly consume some carbs for quick defensive action. So your brain directly impacts your gut.
But information goes both directions. If your gut gets really upset — maybe you’re eating something you’re intolerant to or allergic to — this also sends a message to your brain to kick on that survival response, to power up the inflammation response, and to defend itself. So in that way the brain and the gut interact in a mutual feedback loop.
When you’ve just finished an amazingly delicious meal with close friends, that satisfying feeling in your gut can trigger waves of pleasure and relaxation and send a message to your brain to calm down.
How The Brain Gut Axis Impacts Emotions
The gut also literally processes emotions. So every emotion has a brain component and a gut component. And you’ll notice this in our common language. Notice how many emotions are described as a gut feeling: a kick in the gut, gut-wrenching, sick to my stomach, butterflies in the stomach, etc. So your gut and your brain, again, are closely connected.
During sleep and when we dream, the gut reacts to emotions and processes them. (3) The gut literally works through the feelings of the day. So when the brain is healthy and works through emotions, the gut can process emotions too. And vice versa.
We can help our gut be healthier by decreasing stress and increasing positive experiences, and we can help our brain be healthier by improving our gut health. And one of the best ways to do that is to foster a healthy microbiome.
Your Microbiome Is A Critical Component Of The Brain Gut Axis
So your gut microbiome consists of flora, like fungi, and fauna bacteria that help you digest and absorb food and stay healthy and happy. Diet, age, medications including antibiotics and SSRIs, stress, sleep, and exercise can all negatively or positively impact gut bacteria.
People with anxiety and depression have a different gut microbiome than people who are healthy. They have a higher amount of bad bacteria that can send inflammation into the body and the brain. (4)
Improving your microbiome diversity directly impacts your mood. So how can we do that? Here are four-and-a-half ways to improve your microbiome.
The first one is prebiotics.
Most people have heard of probiotics, but prebiotics are actually very influential. Prebiotics are essentially dietary fiber, the fibrous bits of food that we can’t digest. This is what our gut bacteria lives on.
So for example, some of the good bacteria eat fiber from carrots, and others eat fiber from beets. To foster a healthy and varied gut microbiome, we need to be feeding our good bacteria a wide variety of plants. One study found that prebiotics decrease cortisol, a stress hormone. (5)
So real quick, let’s hear from Dr. Nikki Dinezza how we can improve our prebiotic intake.
“There was a really neat paper a few years ago where they actually were able to give us more of a definitive number. It seems like the number is 30 per week. If you could get 30 different fruits, vegetables, nuts, seeds, whole grains in your diet, different fiber sources — if you can hit that mark of 30 each week consistently, that is very well correlated with better microbial health, better diversity and better richness in the gut microbiome, and better overall health outcomes.”
Number two is probiotics. This is eating foods that already include good bacteria. So this means eating fermented foods like yogurt, kimchi, kefir, and kombucha. And probiotics work best on an empty stomach.
There’s also a lot of probiotic supplements and a ton of companies offering to test your poop and sell you a customized probiotic supplement. Unfortunately we just don’t have enough data to know which types of probiotics help which types of people yet, so I would just be a little bit wary of claims otherwise, especially claims that involve selling you something for the rest of your life.
That being said, some probiotic supplements may be helpful at improving depression and anxiety symptoms.
3. Decrease Inflammation
Number three: decrease inflammation. Inflammation is a good thing in small doses. It’s how your body fights off germs and heals wounds. But emerging research is showing that chronic, sustained inflammation can influence inflammation in the brain.
So how do you decrease inflammation in your gut? You can start by decreasing sugar, processed food, and saturated fats, and then you could work with a qualified specialist to explore allergies and intolerances.
Another thing to consider is the Mediterranean diet. It’s one of the most researched approaches to improving mental health. And a strict adherence to the Mediterranean diet is associated with a 35% decreased risk of depression.
4. Decrease Stress
Number four: decrease your stress. The brain and the gut interact in a cycle. When you do the work to decrease your stress levels, you can decrease inflammation, you can improve your digestion, you can start a positive upward spiral, both mentally and physically. If you don’t know where to start, I’ve got a free course, Grounding Skills for Stress, Anxiety, and PTSD.
4.5 Fecal Transplant
Here’s the last one. I’m not even going to count this one as an option, but it kind of is.
Now, as I said before, emerging research is showing that people with depression have a different gut biome than healthy people. Some research is beginning to show that if you take poop from someone who is healthy and you implant it into the gut of someone who isn’t, that can help them. Unfortunately, we don’t have enough data to know which strains of bacteria are the most important or helpful.
So there you have it: four-and-a-half ways to improve your gut health that may improve your mental health. Have you tried any of them, or are you thinking about it? Let me know in the comments below.
Thank you for reading, and take care.