A Gut Feeling

“Do not think, just go by your gut feeling”; “Having butterflies in my stomach”; “I was scared shitless”; “Do you have the guts to do it?” are popular English phrases in common usage exhibiting a metaphorical link to the gastro-intestinal system. Most of these phrases relate to a basic and fundamental character of human intuition and instinct – responses that are not generally considered to be related to the digestive system. Intuitive responses, though considered illogical and not well-thought of, are primary responses to difficult situations and play a major role in survival of the individual. To this effect, current research has shown that the gut can be regarded as a ‘second brain’ – one that provides an initial response to a situation which is later modified by signals from the higher centres (i.e. brain). It is now well established that the gut after all is not just an organ for producing effluents and letting off odorous gases, but a far more complex organ-system which has far-reaching effects on the entire body.

The gut (enteric) nervous system has up to 30 neurotransmitters (chemicals that help nerves to communicate with each other), most of which are identical to those found in the brain including acetylcholine, serotonin and dopamine. The gut nervous system has more than 50% of the body’s dopamine and up to 95% of serotonin - neurotransmitters which are implicated in mood disorders, motivation, sleep, reward, pleasure etc. Coupled with this, nerves travelling from the gut end up in regions of the brain like the insula, limbic system, pre-frontal cortex, amygdala, hippocampus – areas which are responsible for self-awareness, emotion, morality, fear, memory and motivation. This raises the possibility of signals from the gut having significant influence on such functions. No wonder then, a well-fed individual is a well-minded individual!

Another fascinating aspect of our gut is the presence of the millions (actually up to a trillion!) of microbes (mainly bacteria but also viruses and yeast) making up an ‘ecosystem’ influencing myriad of local and systemic effects which researchers only now are beginning to fathom. There are thousands of species of bacteria which help break down undigested food material and synthesise vitamins (e.g. Vitamin K, components of vitamin B), provide energy to the gut itself, help breakdown toxins and medications, and help influence and train the immune system. Collectively called microbiota, and along with its genome (microbiome) they are now being treated as an independent organ in itself. Dysbiosis – or loss in diversity of the microbiota have been implicated in various malfunctions ranging from diseases such as inflammatory bowel disease (IBD) and irritable bowel syndrome (IBS), metabolic diseases such obesity and diabetes, allergies to neurodevelopmental illnesses.

It is has been shown that a favourable microbial profile is shaped as early as during birth when the bacteria from the mother’s birth canal is translocated to the infant’s gut (infants born by C-section have been shown to harbour unfriendly microbes implicated  in short and long term effects relating to IBS, IBD, allergies etc.). The microbial flora stabilises by the age of three and continues to be affected by dietary patterns, lifestyle, life events, and environmental factors including antibiotic use; forming a unique ‘microbial signature’ which is specific for an individual.

Maintaining a healthy gut isn’t rocket science. Current capitalistic market systems place huge pressure on making profit, which can lead to unethical practices in the food industry with little regard to dangerous health consequences.  It is important to be aware of this and not succumb to  advertising and other media influence. Needless to say, healthy eating habits should start early in childhood with the whole family playing a major role in creating awareness of a healthy lifestyle. There is now ample evidence based on research that a diet that is rich in diverse variety of fresh vegetables and fruits (plant based diet) along with unprocessed (not refined or polished) grains (rice, wheat, corn, millets) can provide for a healthy function of the gut. Another major factor is avoiding processed, ultra-processed and packaged foods that are so temptingly arranged on endless supermarket aisles. Coupled with this, moderate exercise, adequate sleep and balanced mental status will go a long way in ensuring long term health benefits.

Insight in to the non-digestive aspects of the gastro-intestinal system has opened up number of avenues relating to the management of not only Gastro-intestinal diseases but also depressive and anxiety disorders, obesity, autism, Alzheimer’s and Parkinson’s disease. Research in neuro-gastroenterology and the gut microbiota has brought a much-needed boost to the understanding of this rather under-rated organ system when compared to the more glamorous cardiac and neurological systems. So, the next time there is a conflict between the mind and the heart, perhaps It would be wise then to listen to your gut!

Now, there’s some food for thought!