As coaches, we should be asking our clients about the health of their gut. That’s because gut health is intimately related to the regulation of anxiety, mood, cognitive functioning, pain and even changes in brain function.
Until recently, much of the evidence for a gut-brain connection had been anecdotal: psychiatrists had noted that stress-related psychiatric symptoms, such as anxiety, were often accompanied by gastrointestinal disorders, such as irritable bowel syndrome (IBS) and irritable bowel disease (IBD).
After more than a decade of research into the gut-brain connect, much of it with animals, an article published in Nature Reviews Neuroscience in 2012 concluded, “Overall, it is becoming increasingly apparent that behavior, neurophysiology and neurochemistry can be affected in many ways through modulation of the gut microbiota.”
And the recognition that gut health is intimately related to brain health has been accepted by the psychiatric community, as evidenced by a 2015 article in Current Opinions in Psychiatry that noted, “… given the ability of the gut microbiota to influence serotonin and its precursor, tryptophan, regulate the stress response and modulate cognition and behavior, the potential importance of the gut microbiota to psychiatry in general and to depression specifically is apparent.”
If psychiatrists are asking their patients about their gut health, why aren’t coaches asking their clients about the health of their gut?
Let’s get into some of the current research about the gut-brain relationship. Although much of the research has used an animal model, human studies are emerging. Four recent human studies illustrate how gut health is intimately related to brain health, cognitive functioning, and psychological wellbeing.
Schmidt and colleagues (2015) found that participants who took prebiotics (non-digestible carbohydrates, like bananas or oatmeal, that stimulate the growth of healthy bacteria in the gut) for three weeks reduced their anxiety levels. They also decreased their risk of depression and the effects were similar to taking antidepressants or anti-anxiety drugs.
Messaoudi and colleagues (2011) found that participants who took probiotics for 30 days had lowered their risk of depression and increased their problem-solving skills.
Tillisch and colleagues (2013) were the first to demonstrate a direct relationship between gut bacteria and brain function. They found that, after eating yogurt daily for four weeks, the reactivity of the brain to negative emotional facial expressions had decreased.
Finally, Sánchez-Villegas and colleagues (2015) followed 15,093 people over 10 years and found that a Mediterranean-type diet with lots of fruits, vegetables, nuts and legumes reduced their risk of depression. Even small changes in diet had a protective effect.