The Gut and Brain association
There is an overwhelming amount of knowledge that suggests the importance of the gut and the brain connection. The gut is sometimes referred to as “the second brain” as it helps to relieve the symptoms of mental health disorders. The gut and the brain are interconnected in many ways. The good bacteria in the gut contributes to and regulates overall physical and mental health. The primary job of the gut is to break down food and absorb nutrition from it and deficiency in omega 3 or vitamin B is linked with mental health issues.
A Harvard study showed that people with bowel diseases developed mental health symptoms of anxiety and depression (1). Stress affects our appetite and can even kill the good bacteria in the gut. A lot of studies have shown intake of probiotics reduces stress and other mental health symptoms (2). The microbiome-gut-axis is a complex subject that involves the connection between biochemicals, the immune system and nerves. Let’s look at each relationship separately.
1. Nervous System Connection
The gut has its own nervous system that helps it to function independently without requiring the intervention of the brain. This nervous system comprises 200-300 million nerves, hence it receives the name “the second brain.” From releasing digestive enzymes, regulating blood flow and absorbing nutrients, it does it all. The gut uses its own nervous system to function and perform these tasks. Do you know why you get that “gut feeling” when something is about to happen? It's because of the vagus nerve that sends 80% of information from your gut to the brain. Communication starts from the gut and not the other way around.
2. The Biochemical Connection
The neurotransmitter or chemical signals for the happy hormone - serotonin are found in the gut and not in the brain. Research shows that 90% of serotonin is in the gut and not in the brain as it plays an important role in enhancing food movement called peristalsis (3). The bacteria in our gut are the ones that create essential vitamins, minerals and dietary fibre that reach and affect the brain. When you are stressed the stress hormone cortisol tells the gut to secrete compounds that cause inflammation and tiny leaks.
3. The Immune system Connection
A lot of microbes enter our body through our mouth. It's so easy to swallow disease-causing pathogens that eventually end up in our gut. In order to fight these unwelcomed invaders, most of our immunity cells get ready for battle in our gut. The good bacteria wage a war on bad bacteria and this can cause a lot of inflammation. As we know there’s a clear two-way street between the gut and the brain and hence inflammation in the gut results in mood shifts and worsening of mental health issues.
There’s no doubt that the food we eat can drastically make or break our mental well-being. A healthy diet is directly linked to a lower risk of mental health diseases. A nutritious and balanced diet with vegetables, whole grains, legumes, nuts and seeds could improve your gut as well as the brain.