You Are What You Eat
January 02, 2024
Butterflies in the stomach, the sinking feeling of dread, uneasiness of anxiety – different ways that our stomach seems to talk with us. These feelings have been prevalent for a long time and have given rise to many beliefs or superstitions. With the advancement of science, we learned that these feelings come from neurotransmitters in the central nervous system that form a part of the “fight or flight” response. Our digestive system receives signals that suppress our digestion, which allows us to redirect our resources to the danger at hand. This is an evolutionary response to aid our survival, but an overactive nervous system due to stress or anxiety can cause an overreaction which, conversely, impedes our digestive health. Judging from this phenomenon, the mind-gut relationship sounds like a very one-sided controlling relationship. And until recently, this was our understanding of the mind-gut interaction.
What are Neurotransmitters?
With advancements in neurology and neuroscience, we were able to better understand the lifecycle of neurotransmitters and how they are used for communication. Serotonin, which is often targeted by antidepressants, is primarily secreted in the gut and 95% of serotonin in our body is located there. The discovery of how neurotransmitters are secreted was monumental in understanding the wider connectedness of our nervous system. However, this also meant that the focus of mind-gut interactions was purely on neurotransmitters. And while neuroscientists were busy investigating these neurotransmitter glands, there were organisms living in our gut who, unbeknownst to us, had an important role in our neurological functioning.
Gut Microbiome
A microbiome is defined as a collection of microbes, such as bacteria, fungi, and viruses. Microbiomes are found in natural habitats in varying shapes and sizes. One of those natural habitats is our gut. When we think of bacteria and viruses, we tend to remember the last time we were sick or, in the wider scheme, the pandemic we recently lived through. However, not all bacteria and viruses are bad to us. A great example of this is the powerhouse of our cells – mitochondria. A prevalent theory states that mitochondria started as bacteria outside of our organisms and, with time, they entered our organism to create endosymbiosis – a mutually beneficial relationship with us. It is an essential part of both our daily functioning and high school biology curriculum; research is still ongoing to understand which function is more important. Similarly, the mutual communication between our central nervous system and gut microbiome is an integral part of the gut-brain axis.
Probiotics, which make up a part of our gut microbiome and had a claim to fame through yoghurt advertisements, help reduce inflammation when our digestive system experiences stress. Reducing inflammation also restricts the release of cytokines, particularly IL-6 and TNF-a, which contribute to the development of symptoms of anxiety and depression. Animal studies provide more direct evidence of it with mice who received probiotics showing greater neuron generation (neurogenesis) and synaptic plasticity. Increased gut and neuron health also translates to elated mood, as evidenced by human participants with depressive symptoms whose mood increased significantly after a three-week Bifidobacteria treatment. Other probiotics have shown similar anxiolytic and depression symptom reduction symptoms at similar levels of anxiolytic medication. It is important to state that participants of these studies were either healthy volunteers or with controlled depression symptoms. Probiotics are not a replacement for anxiolytic or antidepressant medication. Similarly, nutrients such as vitamin D and B12 have been implicated in anxiety and depression symptom improvements.
While these findings may sound very positive and result in a temptation to buy multiple vitamin and probiotic complexes, the real takeaway of these findings is that balanced nutrition and good gut health are protective factors for mental health and well-being. Probiotics and vitamins are not replacements for treatment, and taking these supplements alone will not stop or cure anyone of anxiety or depression. Here at Mindsum, we care about your overall wellbeing and our therapists are here to listen and support you through your wellbeing journey.