Your brain is a true powerhouse of billions of neurons. These neurons are constantly firing electrical signals back and forth, telling you what to think, what to feel and what to do. But, did you know that we all have a second brain? And, it controls a lot more than you may realize. Any idea where it’s located? In your gut, of course!

Your Controlling Gut

In reality, the gut is an independent center of integrative neural activity. This means that it can work all on its own, without any input from the brain. For instance, it controls the movement and absorption of food through the intestines. No other organ can work independently of any control by the brain in your head.

In general, one of the main ways your brain communicates with the rest of your body is through the vagus nerve. It passes messages to the heart, lungs, digestive tract, and vocal chords. With your gut, it actually passes messages back to your brain.

The Enteric Nervous System

Ever had a gut-wrenching experience? Reached for the ice-cream when you’re stressed? Relied on your gut instincts to make an important decision? These are all prime examples of your gut sending messages to your brain.

Within the enteric nervous system (ENS), the extensive mesh-like network of neurons that controls your digestive tract, messages are being sent to your brain. In fact, 80% to 90% of nerve fibres in the enteric nervous system are going from the gut to the brain. The ENS contains an astonishing 100 million neurons, which is a lot fewer than your brain but more than the spinal cord.

Your ENS Influences Your Mood

You may be saying, okay, the gut sends messages to your brain, but that doesn’t mean it’s in control. Wrong! It turns out that our digestive system also influences our choices on a daily basis. Research has shown that our gut can manipulate food cravings and behaviour to ensure their own survival. In addition, colonies in our digestive system also affect our mood.

For instance, it sends signals north to the brain that directly affects feelings of sadness or stress, even influence memory, learning and decision-making. It manufactures more than 30 neurotransmitters. This includes serotonin that is identical to the one found in the brain.

Recent studies have also revealed that the second brain in our gut can also be a powerful tool for achieving major relief from depression. People with healthy and diverse microbiomes are less likely to be depressed or anxious. Research conducted on rats also shows that gut bacteria can change feelings and behaviour. For instance, rats inoculated with bacteria from depressed people started to develop signs of depression themselves.

The ENS and Autism

Even autism, studies suggest, may be wrapped in the neurobiology of the brain below your head. Researchers found that mice who grew up in sterile environments – where no bacteria colonized their gut – displayed social traits similar to humans on the autism spectrum. When these mice were fed probiotics, however, their symptoms were alleviated.

This kind of effect has also been seen in studies with humans too. Many scientists, therefore, now believe that one of the primary functions of gut bacteria is actually to promote social behaviours. This ensures survival of the species through sexual reproduction.

To a certain extent, it appears that our second brain is even more influential than our logical thoughts. So, the next time your gut sends you a message, it might be best to listen to it!

‍