Recent years have seen a growing awareness of mental health issues, and, thankfully, more open conversations about addressing psychological challenges. However, many people remain unaware of new, exciting research on the connection between gut health and mental health. The connection between your digestive system and your brain can have a profound influence on your mental health, thanks to the complex communication network that exists between the two.
It may initially seem like a stretch to say your gut health affects your mood. So, let’s take a step back to look at the key terms. Your body’s organs do not exist in isolation, but rather are connected through complex networks that enable communication. Neurons are central to this process. They facilitate the communication between your brain and the rest of your body, everything from muscle reflexes, digestion to thoughts and emotions.
Neurotransmitters are the body’s chemical messengers, responsible for transmitting messages from neuron to neuron. When it comes to our mood regulation, an imbalance of certain neurotransmitters can result in mood disorders. Serotonin is one of these powerful neurotransmitters that regulates your mood, and a shortfall of serotonin can lead to depression.
The Autonomic Nervous System (ANS) has three branches: the sympathetic nervous system, the parasympathetic nervous system and the enteric nervous system. The parasympathetic nervous system works to maintain homeostasis in the body and slow things down, while the sympathetic nervous system kicks in when there’s a threat or crisis and speeds up bodily functions. A good way to remember the difference is that the sympathetic nervous system works for “flight or fight” responses, and the parasympathetic is “rest and digest” responses.
One of the largest connections within the nervous system is the vagus nerve (also called the pneumogastric nerve), which sends two-way messages between your brain and your digestive system. The vagus nerve is part of the enteric nervous system, which independently controls functions of the gastrointestinal tract without input from the Central Nervous System (CNS) - the connection between the brain and spinal cord which controls most functions of the body and mind.
Disturbances in the balance between nervous systems can lead to physical problems that are triggered by a psychological component - like stress triggering IBS symptoms. The vagus nerve helps with the parasympathetic nervous system to keep your body in “rest and digest” and helps to slow down the flight or fight responses that can wreak havoc on mental and physical health. Studies show that poor vagal tone can lead to difficulties regulating emotional responses.
Your gut is also a microbiome for trillions of microbes, which are bacteria, fungi and even viruses. These microbes play a large role in your health, including your mental health. They’re responsible for most of the production of the “happy” neurotransmitter, serotonin. The microbiome also helps produce gamma-aminobutyric acid (GABA), which is a neurotransmitter that regulates anxiety. Some studies have found that gut microbiomes can also activate the vagus nerve (more on activating the vagus nerve below!)
As you can see from all the “messengers” described above, your brain and your gut have constant bi-directional communication. That explains the queasy feelings that accompany nervousness (or even love!). But it’s important to remember that communication flows both ways. Disturbances in your gut can affect your brain, and as a result, there is a profound correlation between your gut bacteria and your mental health. Imbalances in the microbiome can reduce serotonin production.
Optimum gut health depends on many different factors, but one thing we can control is the food we eat. Studies suggest that diversity of microbes offers the best protection, and your diet can play a role in creating this diversity. Unfortunately, the typical North American diet of processed foods doesn’t typically have a lot of diversity. The following foods can help increase bacteria.
A few lifestyle changes to incorporate to help optimize your gut health and improve mental health include:
New research is being done regarding natural vagus nerve stimulation (without the electronic impulses done in a clinical setting). This helps to “tone” the vagus nerve to improve its function, and, therefore, your ability to slow the fight or flight response. Studies have shown that people with a strong vagus respond better to stress. To activate your vagus nerve:
Protecting your mental health is best approached with a multifaceted approach that includes optimizing your gut health. While it is also important to maintain your optimal hormone levels and other processes in the body for your mental health, keeping in mind the importance of what you feed your body also key in achieving your best.
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