Hippocrates, the Greek physician who is considered the ‘father of modern medicine’ (460 – 380 BC), famously stated that: “All disease begins in the gut.”[1]
This is as true today as it was back then. Modern science continues to find new evidence that many diseases do indeed originate in the gut – which is comprised of all the digestive organs from the mouth to the anus, also known as the gastrointestinal tract (GI tract).
In addition to the key sites of digestion and elimination like the stomach and intestines, there is also the liver which is considered one of the ‘accessory digestive organs’. So if the liver is not working properly, the gut cannot function correctly.
Also located within the gastrointestinal tract are the lymphatic vessels and glands which form a major component of the human immune system. This is one reason why gut health is so intimately connected with immunity, and why a stressed digestive system can lead to chronic inflammatory bowel disease and chronic infections like candida.
More specifically, current research is indicating that the chronic inflammatory bowel diseases – Crohn’s disease, colitis, celiac disease, and irritable bowel syndrome (IBS) – are the result of a combination of factors that include leaky gut syndrome, the invasion of pathogenic microorganisms such as candida yeast, as well as an immune system weakened by internal and external factors.[2]
Leaky Gut Syndrome
Over time, due to a number of modern dietary and lifestyle factors, the gut begins to malfunction and weaken. These causative factors include chlorinated drinking water which works to kill not only the parasites in tap water, but also the ‘good’ bacteria in our guts. In addition, chronic stress, prescription medications, overeating, high sugar consumption, and the presence of pathogens (moulds, yeasts, fungi, and their poisons) are other key factors.
The result of such toxic exposures is inflammation of the intestinal mucosa that lines the digestive tract, leading to a ‘leaky gut’ characterized by open spaces between cells of the intestinal tract. This in turn allows for large-sized proteins, undigested food particles, and poisons in the bowel to ‘leak’ directly into the bloodstream and, as foreign molecules, they challenge and weaken the immune system over time.
According to Dr. Zoltan Rona, MD, about one in seven individuals have ‘leaky gut’ as an underlying factor that contributes to their gastrointestinal illness.[3] Because toxins that leak through the intestines can travel to tissues and organs throughout the body, many health problems may not appear to be correlated to a leaky gut at first glance. Such symptoms can manifest in any system of the body from the brain and endocrine system to the immune system. Symptoms of leaky gut syndrome can include depression, fatigue, general malaise, bloating, chronic infections including candida yeast infections, food sensitivities and allergies, and even autoimmune disease.
How Gut Health Affects Mental Health – for Better or Worse
In addition to the role played by the gut in our immune defences, it is also the location where over 70% of our neurotransmitters are created (one of the reasons it’s known as our ‘second brain’). As a result, a major group of symptoms related to leaky gut syndrome includes mental health issues such as anxiety and depression. This is because proteins and toxins leaking into the blood can find their way to the thyroid or hypothalamus in the brain[4], disrupting mood and energy. Furthermore, the neurotransmitters created in the gut must be properly absorbed through a healthy intestinal lining. If the intestinal lining is damaged, insufficient amounts of these neurotransmitters are properly absorbed.
The challenge is further compounded when you factor in the amino acids we need as precursors to neurotransmitters (like tyrosine which makes dopamine and norepinephrine), that must be absorbed through the gut before entering the brain[5]. Often, the role of the gut is overlooked when it comes to mental health, and mental health symptoms can be overlooked as symptoms of gut health issues. Interestingly, Dr. Michael Gershon, of Columbia University Medical Center, an expert on the gut-brain connection, has shown that 95% of all serotonin in the body is found in the GI tract.[6]
Issues with neurotransmitter synthesis and poor absorption in the gut due to inflammation can be made worse by the presence of mycotoxins caused by bacteria and parasites. These types of toxins are produced in the bowel and cross through the blood-brain barrier.
By reducing inflammation and healing a leaky gut, neurotransmitters can be properly absorbed and get to their final destination – the brain.[7] In turn, proper neurotransmitter synthesis and absorption is vital for supporting the parasympathetic nervous system response required to run the digestive processes of the body. Alternatively, when the body is under stress and the central nervous system is hyperstimulated, digestion is hindered and the vicious cycle of inflammation and its effects on ‘leaky gut’ continues forward.
Simply put, you cannot have a clear brain if you don’t have a clear gut. And if there is a deficiency of the valuable neurotransmitters that promote wellbeing, then the stress produced in the body will immediately start to impact digestion.
