While we might think of only seeing a mental health professional for issues related to thoughts, feelings, mood and emotions, our physiologic state of health also has a big impact on our mental and emotional well-being. Some medical conditions are well known to contribute to mental and emotional issues — hypothyroidism causing depression, some infections or autoimmune processes contributing to anxiety or obsessive and compulsive thinking, or head injuries leading to mental health issues, to name a few. But less commonly do we think about addressing digestive health problems, for example, as a strategy to help improve depression or anxiety.
Research and clinical evidence continue to illuminate the connections between physiologic and metabolic health and the health of our brain. It makes sense, as the brain is a very energy-hungry organ, consuming about 20% of the energy of our entire body, and relies on the health of the rest of the body for optimal nutrition and hormone balance. The functioning of the mitochondria, the machinery of our cells that creates energy, requires both proper nutritional input and enough oxygen to function well, and if these are not optimally available, it will compromise brain health and function. A growing body of doctors and researchers are drawing connections between mitochondrial function and mental health.
The state of health of the digestive system may be even further "upstream," having a tremendous impact on many areas of mental health. One piece of this has to do with levels of inflammation present in the gut. If the digestive tract is chronically irritated and inflamed it will lead to inflammation elsewhere in the body, including the brain, and can contribute to brain fog, low energy, anxiety and depression. This inflammation can be the consequence of a poor diet —too much sugar, alcohol and other pro-inflammatory foods. It can also be the result of more serious auto immune illnesses like Crohn's or ulcerative colitis, both understood to contribute to mental health concerns.
Neurotransmitters that were at one time thought to be only associated with brain function are now understood to be a huge part of the function of our digestive systems. In fact, the majority of the body's serotonin production occurs in the gut, not the brain. Additionally, dozens of other neurotransmitters are active in the gut, and the connections between the brain and gut are so extensive, that the gut has been referred to as the "second brain." While many of these neurotransmitters are affecting digestive system function, there is also a tremendous amount of communication between the gut and brain, impacting mood, thinking and emotional well-being.
Much of this physiologic activity is mediated also by the landscape of microorganisms that live commensally in our gut. This ecosystem, referred to as the microbiome, is so vast that it is estimated we have 10 times as many microbes in our gut than we have human cells in our entire bodies. Research over the last couple of decades continues to confirm that the balance or imbalance of this complex microflora has major implications for our health, our immune systems, optimal digestion, synthesis of neurotransmitters and the functioning of our brain.
Studies have demonstrated that certain strains of Lactobacillus (beneficial gut microorganisms or probiotics) for example, can help to increase the production of GABA, a neurotransmitter that calms fear and anxiety. Other strains of beneficial probiotic microbes like Bifidobacterium are being shown to alleviate symptoms of depression. The degree to which the gut microbial ecosystem is impacting brain health, mood, emotions and cognition is so profound that the term "psychobiotics" is now found in the scientific literature — literally meaning probiotic microbes that affect our psyche.
While seeking help from therapists, psychologists and other mental health pros is obviously very important, a complete approach to mental health also means a thorough conversation with your holistically minded doctor about physical health. Addressing issues of gut flora imbalances, and sources of GI irritation and inflammation can be a very important part of the puzzle, addressing issues like anxiety and depression, helping to improve mood, emotions and cognition.
—Joshua Phillips, ND is a naturopathic physician and director at Hawthorn Healing Arts Center in Bend. This article is not intended as medical advice, but for informational purposes only.