Your gut is the cornerstone of your immune system

Your gut is the cornerstone of your immune system

The intestinal wall covers a surface area of approximately 200m2, more than 100 times the surface area of the skin. Its cells regenerate continuously in a 72-hour cycle. This dynamic organ consumes about 40% of the body’s energy expenditure. Once thought as a site of digestion, nutrient absorption and excretion, the gut turns out to exert critical biological functions by regulating the traffic of molecules between the environment and the host through a barrier mechanism. The single layer of cells lining the gut lumen is the primary interface between the outside world and ourselves. This is where the body decides what to call “self” and what to call “other” and what is allowed to enter and what is rejected. As the gastrointestinal mucosal immune system, it controls our immune reactions whether to be alerted or be quiescent. 


More than 70 per cent of the immune system resides in the gut lining with its inhabitants, 100 trillion microorganisms. Normally these bacteria, yeasts, parasites forming a unique ecosystem, co-exist peacefully without eliciting chronic inflammation. When there is a threat from pathogens, they provide a measured inflammatory and defensive response. 

In order to maintain the system, immune cells carry out surveillance and eliminate damaged or dangerous cells such as cancer cells. Activation of the immune system normally serves to fight invaders or clear cellular junk but that can get out of control. An over-aggressive immune system is not desirable and should be balanced with suppression, otherwise, any organ or tissue could be targeted. Autoimmunity typically results from the loss of the regulatory T cells or Tregs, immune cells that keep the overzealous immune system in check. For good health, effective suppression of the aggressive immune system is essential.

Untamed T killer cells in action can manifest as degenerative autoimmune diseases, such as arthritis, coeliac, Hashimoto’s thyroiditis and inflammatory bowel diseases. This can affect fertility badly at many levels. Ovaries, adrenal glands, thyroid and other hormonal glands can be attacked by autoimmunity, implantation of the embryo can be hindered with many cases of recurrent miscarriages and unexplained infertility revealed to have a component of immune malfunction.  Taming autoimmunity and achieving immunological tolerance will contribute to the prevention of premature degeneration and will help improve fertility and the likelihood of successful pregnancy outcomes.


Universal mechanism of diseases

Immune cells in the gut lining continuously develop and control immune reactions. Maintaining the integrity of this gut lining is dependent on the gut flora as they repair the lining, develop immune cells and drive the inflammatory balance. Damaged gut lining, resulting in a loss of barrier function and increased permeability is now recognized as a universal mechanism underlying the development of a wide range of diseases. 


The right place to focus on

A lot of the clients that come to my practice exhibit some level of digestive imbalance. Whenever we eat, an immune reaction is induced and immune cells and gut bacteria are mobilised. Consumption of processed foods lacking prebiotic fibre while laced with sugar, refined starch, rancid seed oil, food additives produces gut dysbiosis- a disruption of the gut microbial community. Use of antibiotics, birth control pills and other forms of synthetic hormone cause dysbiosis. The use of the painkiller NSAID erodes the gut lining. Many pharmaceutical drugs have antibiotic properties as they kill and alter bacteria in the gut. All these necessitate the recovery of the gut flora and the replenishment of the gut lining, otherwise, food intolerances, allergies, autoimmunity, localized/systemic inflammation can ensue. 


The condition of the gut can be seen as a proxy of how well we fare in the given environmental factors. Diet is a major one but other lifestyle factors such as movement, stress, relationship, sleep, air, sun exposure, thoughts, etc all register here and play a part in either restoring or losing gut health. The gut can open the floodgates to diverse illnesses but it can serve as a gateway to healing these illnesses from their roots. This poses a striking contrast to the conventional ‘symptom modulation’ or ‘one pill for one illness’ approach.


Hippocrates said ‘All disease begins in the gut’ and this is as true today as it was two thousand years ago.