How Exercise and Mental Health are Connected
I’m sure at some point in our lives we’ve all heard something along the lines of “a healthy body makes for a healthy mind.” While this might come across as simply a nice sentiment or common sense, the research supporting this claim is fascinating. In recent years, scientists have begun to reveal more and more on how exactly our minds and bodies work together to benefit each other. Earlier we examined how building our body’s muscle strengths can improve our brains strength as well. A study conducted on twins revealed that the twin with stronger leg muscles also had stronger cognitive abilities. The results from this study indicated that how we live and how we take care of our bodies can determine how we store information, since our bodies are, in essence, one large information system. To put it simply: we are our brains. But here may be more to the correlation between mind and body may be even more intricate than we previously realized. In fact, as it turns out, regular bodily exercise can actually alter our physical chemistry which can result in better mental health. How? The answer lies in the microbes found in our stomachs.
Is The Key to a Healthy Mind Through Our Diet?
There have been a wide number of animal studies which have revealed a definite correlation between gastrointestinal pathology and certain psycho-neurological conditions including but not limited to: autism, anxiety, depression, and schizophrenia. In fact, since 2013, the National Institute on Mental Health has dedicated millions of dollars towards funding seven different studies attempting to examine what scientists refer to as the “Microbiome – Gut-Brain-Axis.” These studies confirm that our brains respond to microbial signals from our guts. In one instance, researchers from McMaster University in Hamilton, Ontario found that intestinal bacteria can play an important role in reducing anxiety and depression. Their findings were published in July 2015 in the scientific journal Nature Communications where they found that “MS-induced changes in host physiology lead to intestinal dysbiosis, which is a critical determinant of the abnormal behaviour that characterizes this model of early-life stress.”
In other words, the induced changes in the way the test subject’s physiology – their physical make-up – caused an imbalance in intestinal bacteria. This, in turn, lead to abnormal behavior indicative of stress and anxiety. Another study, led by Elaine Hsiao, a biologist now working with UCLA, revealed that certain metabolites from gut microbes promote serotonin production in the cells which lined the colon. What does this mean? Well, one of the most common forms of antidepressants, SSRI (Selective Serotonin Reuptake Inhibitor), are purposely designed to target serotonin reuptake at the junction between neurons. Through this, they treat depression by reducing an imbalance in serotonin production that may cause it. Serotonin has been shown to improve the development of new brain cells which can alleviate depression since depression can in many cases effectively suppress this production. In essence, serotonin helps promote healing, which can ultimately lead to a sense of well being and happiness. It is interesting, then, that the majority of the body’s serotonin (around 90%)can be found in the human digestive tract, regulating gut movement.
The Relationship Between the Human Mind and Body
Currently, more research is needed to truly determine the extent of the relationship between our minds and bodies, particularly where chemicals such as serotonin are involved, since their roles are often multifaceted and complex. However, the growing body of evidence suggesting correlations between mind and matter is fascinating and can help us discover new ways to improve our overall health and wellbeing. That being said, there is surmounting evidence which suggests that exercise, especially in early-life, can alter the microbial community in our guts which can then promote good brain health and metabolic activity throughout the course of our lives.
While we don’t yet know the exact age range that our gut microbes are most susceptible to early-life changes in exercise, preliminary findings suggest that the earlier the better. After all, unhealthy habits developed while we’re young can be some of the most difficult to break later on, sedentarism included. Moving forward, scientists hope to find how the relationships in this microbial ecosystem impact brain function in a long-lasting way. By doing this, we can eventually hope to encourage gut-microbe plasticity in adults which can then help combat the high rates of anxiety and depression within that community. While further investigation is needed toward this goal, the future looks promising.