Ever trusted your gut instincts to make a decision or felt those nervous butterflies in your stomach? Or consider why something upsetting can feel so "gut-wrenching"?
Turns out, those feelings aren't just bodily quirks. Your digestive system houses a “second brain.” Nestled within the walls of the digestive system, this “brain in your gut” is transforming how medicine understands the complex interplay between gut health, emotions, and mental well-being.
In healthcare, Scientists call this “little brain” the enteric nervous system (ENS). The ENS is quite extensive, comprising two layers with over 400-600 million nerve cells that line the entire digestive tract, from your throat to your rectum. Whether you're feeling angry, anxious, sad, or joyful, these emotions can all cause symptoms in your gastrointestinal tract (GI tract).
The connection between the brain and the gut goes both ways. For instance, simply thinking about eating can trigger the stomach to start producing digestive juices, even before food arrives and an upset intestine can send signals to the brain, just as a distressed brain can affect the gut. As a result, stomach or intestinal issues can be either the cause or the result of anxiety, stress, or depression.
But How Are They Connected?
The connection between your gut and brain involves both physical pathways and chemical messengers:
1. The vagus nerve: This nerve acts like a direct phone line between your brain and your gut, allowing them to communicate. It allows signals to travel back and forth, influencing functions like digestion, mood, and even immune responses.
2. Neurotransmitters: These are chemical messengers that travel between your gut and your brain, influencing various processes. For example, serotonin, a neurotransmitter primarily known for its role in mood regulation, is also found in high concentrations in the gut, where it helps control gut movement and function.
3. The gut microbiome: Your gut hosts a complex ecosystem with trillions of microorganisms, including bacteria, viruses, and fungi. They help break down food, absorb nutrients, and the synthesis of many vitamins and compounds. Moreover, research indicates they can also produce neurotransmitters and other bioactive molecules that affect brain function and behavior, contributing to the gut-brain axis.
Now that you know how closely the gut and the brain interact, it's easier to understand why we might feel nauseous before an exam or have stomach pain when stressed.
How Can This Negatively Impact Us?
People often dismiss functional gastrointestinal conditions as imaginary or purely psychological, but both psychological and physical factors contribute to bowel pain and symptoms.
Intense emotions can speed up or slow down GI tract movement, increasing sensitivity to bloating and pain signals. In more technical terms, such sensitivity allows bacteria to cross the gut lining, activating the immune system, escalating inflammation, and altering the gut microbiota.
Therefore, feelings like stress can exacerbate GI conditions like inflammatory bowel disease (including Crohn's disease and ulcerative colitis), irritable bowel syndrome (IBS), gastroesophageal reflux disease (GERD), and food allergies and sensitivities.
Exploring Treatment Avenues
Given what we understand about this link, it's clear that mind-body approaches such as meditation, breathing exercises, yoga, and gut-directed hypnotherapy have all been shown to help improve GI symptoms, improve mood, and decrease anxiety.
Doctors are prescribing antidepressants for treating IBS and bowel-disorder treatments as these medications can calm the symptoms in some cases by acting on nerve cells in the gut and improve GI tract motility.
Certain foods can trigger specific reactions in the gut of sensitive individuals. In such cases, following specialized diets like low-FODMAP for IBS or avoiding acidic foods can effectively manage symptoms.
Edited by Harshajit Sarmah
