A large body of evidence is accumulating to support a role between healthy gut function, brain development and function of the central nervous system. The organisms contained in the gut should be considered an inner organ with functions similar in importance to any other organ present in the body. Disruptions in this “organ” may alter many things including brain function and cause symptoms like depression, anxiety, ‘brain fog’ and more.
At birth the human gastrointestinal tract is sterile, however, it is quickly colonized and by the age of one year, the bacterial profile looks similar to that of an adult.1 The connection between the gut and the brain is known to be bidirectional. This means messages from the gut affect brain function just as much as messages from the brain affect gut function.2
The mechanism by which alterations in bacterial profiles of the gut affect how we feel, think and move is fascinating. It all begins with lipopolysaccharides (LPS). LPS are structures located on the surfaces of bacteria present in our gut. These LPS may actually get out of the gut and into the blood stream producing a very strong immune response. Normally, the gut does a very good job keeping these LPS from getting into the blood stream.3 However, when the barrier in the gut weakens (‘leaky gut’) LPS is more easily absorbed and enters circulation. When this occurs, inflammation ensues. If the process continues, high levels of inflammation are generated and this begins to alter neurotransmitter levels in the brain. With enough change in neurotransmitter levels, mood, behavior and cognitive function suffer.
What causes leaky gut? There are a lot of factors, however, evidence points to a high fructose diet (sugary beverages), the Western diet (high in processed foods) and nutrient deficiencies like vitamin D, A, zinc and magnesium.These factors are also known to increase the ability of LPS to get into the blood stream.4
Symptoms of depression, anxiety, ‘brain fog,’ or poor memory may not always be coming from your brain. The genesis of the problem might actually be in your gut! By maintaining a healthy diet and addressing potential nutrient deficiencies you may see many of your symptoms disappear without the need for expensive, mind-altering medications!
1Palmer C, Bik EM, DiGiulio DB, Relman DA, Brown PO. Development of the human infant intestinal microbiota. PLoS Biol. 2007 Jul;5(7):e177.
2O’Mahony SM, Hyland NP, Dinan TG, Cryan JF. Maternal separation as a model of brain-gut axis dysfunction. Psychopharmacology (Berl). 2011 Mar;214(1):71-88.
3Bested AC, Logan AC, Selhub EM. Intestinal microbiota, probiotics and mental health: from Metchnikoff to modern advances: Part II – contemporary contextual research. Gut Pathog. 2013 Mar 14;5(1):3.
4Teixeira TF, Collado MC, Ferreira CL, Bressan J, Peluzio Mdo C. Potential mechanisms for the emerging link between obesity and increased intestinal permeability. Nutr Res. 2012 Sep;32(9):637-47.