Your Brain and Gut Talk to Each Other — It’s Time We Paid Attention!

Butterflies in your stomach?

No appetite when you’re stressed?


These happen because two parts of your body (parts that you’d least expect!) talk to each other — your brain and gut.

The gut–brain axis involves a two-way communication network between your central nervous system in your brain and your intestines. This communication is very complex, and researchers still have a lot to learn about it.

But don’t worry, Dr. YOU is here to simplify how your gut and brain are connected.

What do you mean, ‘talk’ to each other?

Good question!

Let’s first understand what the enteric nervous system is. It’s the large network of neurons present in your gastrointestinal tract. Because it’s so massive and complex and can act without inputs from the brain, the enteric nervous system is called your second brain.

This is probably how the phrase “trust your gut” came about!

The bacteria in your gut play an important role in the gut–brain axis. They not only interact with the cells lining your intestines and the enteric nervous system, but also directly with your central nervous system.

The microbes in your gut can make special molecules that affect the gut–brain interaction. These neurotransmitters can influence how your brain cells function.

Sometimes the conversation is happy

We were wondering when you’d ask!

Here’s an example: serotonin (or the happy hormone) is an important neurotransmitter involved in various functions in the central nervous system, like regulating your mood and behaviour.

Did you know that your gut produces 90% of your serotonin?! Maybe that’s why what you eat affects your mood so strongly.

Your gut also produces 50% of dopamine (the pleasure-seeking hormone), melatonin (the sleep hormone), and oxytocin (the love hormone). So when there’s an imbalance in your gut bacteria, your mood and behaviour may be negatively affected.

Sometimes it isn’t!

No surprises here, but stress, even for a short while, can fire up complex pathways in your brain that affect your gut bacteria. Stress activates the hypothalamic–pituitary–adrenal axis, a part of the limbic system in your brain that’s involved in memory and emotion.

This releases cortisol (the stress hormone) from the adrenal glands. Cortisol and your central nervous system work in parallel to target the intestines, resulting in the “gut feelings” you get when you’re stressed.

Your gut bacteria can also affect your risk of certain brain-related disorders like Parkinson’s disease, Alzheimer’s disease, and autism. For example, your gut bacteria makes a substance called synuclein that can travel to the brain via the nerves. This substance has been found in the brains of people with Parkinson’s disease.

But it’s always worth listening to!

Dysbiosis is an imbalance in your gut microbial community that can lead to undesirable health outcomes. In addition to immune-related disorders like inflammatory bowel disease, type 1 diabetes, and rheumatoid arthritis, dysbiosis can impact the blood–brain barrier.

The blood–brain barrier is highly selective about what substances can get close to the brain. Dysbiosis may affect how well the blood–brain barrier works. This can lead to unwanted substances reaching the brain, resulting in inflammation.

We hope you appreciate how valuable this crosstalk is between your gut and brain. So, it’s time to start looking after your brain for your gut, and look after your gut for your brain!

Check out ways to maintain a healthy gut in our previous blog.

Remember, the only person who can keep YOU the healthiest is YOU!

DISCLAIMER: Dr. YOU aims to bring you the latest evidence-based science, and our content is for informational purposes only. The content is not medical advice or guarantee of an outcome. You should always consult a doctor or qualified healthcare professional if you need further clarification and before making any changes to your treatment plans and lifestyle, or that of others.

Dr. YOU is a one-stop platform to address the health information needs of health consumers. Our goal is to arm people with the information necessary to make meaningful decisions regarding their health and nudge behaviour change.

With our combined experience of two decades in research and healthcare, we built the Dr. YOU platform around the WHO-endorsed “Best Buy” intervention design for preventing and managing chronic diseases.

Follow us on Medium (@drYOUofficial) and Instagram (@dr.YOU_official) for the latest content and updates.



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