Updated: Jun 22, 2020
Research over recent years has shown that our gut bacteria is fundamentally linked to our health and well-being. Another area where gut bacteria is being investigated is in the functioning of the brain. This new field is referred to as psychobiotics and it is helping scientists understand the way that gut bacteria communicates with our brain.
Scientists have discovered a number of ways that bacteria and brain communicate. The first is via the vagus nerve which the nerve that connects most of the organs in our body. The vagus nerve sends messages from the brain to the gut but far more messages from the gut to the brain. The second way is production of short chain fatty acids that are produced by the gut bacteria. These fatty acids are absorbed into the blood stream and travel to the brain. It is still unclear how this affects the brain. The third way is the production of tryptophan by the gut bacteria, which is a precursor for the production of the hormone serotonin, otherwise known as the happy hormone, because it helps maintains mood and sleep. Tryptophan is normally found in carbohydrates and turkey!! The more tryptophan we have the more serotonin we produce and the calmer we feel.
What scientists have also discovered is that people who suffer from anxiety and depression have less diversity of gut bacteria. Better health is link to greater diversity of bacteria in the gut. There are two main types of beneficial bacteria in the gut. These are lactobacillus (L.) and bifobacterium (B.). Lower levels of lactobacillus are correlated with poor sleep which is often a symptom of depression. Lower levels of bifobacterium are associated with high levels of the cortisol hormone. This hormone is a marker used to determine stress levels withing the body.
How then, can we increase the numbers of our beneficial bacteria and improve brain function?
First and foremost we need to assess our diet. A diet high in sugary foods and drinks, processed foods and refined grains such as white rice, pasta and bread has a detrimental affect on the both mood and gut bacteria. Reducing these foods to the occasional treat may help both mood and bacteria. Replacing white bread, pasta and rice with wholegrain equivalents may help.