Anxiety, depression and other mood issues are not all "just in your head" more and more studies now show that these mood changes could be symptoms of what is actually happening inside your gut
So how does the gut affect our brain?
Serotonin : Up to 90% of our serotonin is produced in the gut and directly affects mood signalling in our brain
Immune system cytokines : The intestinal microbiome can prompt immune cells to produce pro inflammatory cytokines that can induce anxiety and depression
Vagus Nerve : Is a direct connection from the brain to the gut, Vagal tone (how strong it is) can affect emotional regulation, depression and even act as a persons measure to how sensitive they are to stress.
gut-brain connection and what are the triggers
So, what can trigger the mechanisms of the gut-brain connection as mentioned before?
An Unhealthy Microbiome (DYSBIOSIS)
Studies have demonstrated that the collection of microorganisms living in our gut influences stress reactivity and anxiety-like behaviour. Recent research examined the composition of gut bacteria in patients with depression compared to healthy individuals and reported significant differences with increased population of Bacteroidetes, Proteobacteria, and Actinobacteria, and decreased population of Firmicutes in patients with depression
Pathogens
Pathogens are the bad guys - things like specific strains of overgrown yeast, bacteria and parasites that shouldn’t be living in our gut. It is now accepted that gut infections can cause anxiety, depression and cognitive dysfunction.
Food
Food and mood are connected in many different ways. Overeating and obesity is often associated with depression and anxiety, although this may have less to do directly with the food we eat and more to do with our microbiome. But also the way in which we use certain ‘comfort’ foods to try and regulate our mood and the effect of certain foods on pleasure and reward regions of the brain.
Leaky Gut
According to recent scientific findings, increased intestinal permeability may underpin the chronic low-grade inflammation observed in disorders such as depression and may have further negative effects on mood, anxiety, cognition and social interaction.
Reflux
Hydrochloric acid (HCl) produced in the stomach is essential for killing bacteria, fungi and parasites that come in on our food and water. Low levels can weaken immunity and, in turn, lead to many of the problems listed above including the inability to break down foods and kill gut infections before they can enter the GI tract. This may explain the connection between those with depression and reflux conditions like GERD.