Last week we addressed the controversial subject of leaky gut, which has become the “go-to” underlying cause for many chronic diseases by many alternative practitioners. Gastroenterologists are also now acknowledging that there is increasing evidence of a condition they refer to as increased intestinal permeability. In this condition the tight junctions between the cells lining the intestine are impaired, and this allows larger proteins and bacteria to enter into the blood stream.
The big difference between gastroenterologists and others is in the emphasis placed on this condition, and the identified causes, as well as dietary interventions to manage it.
Many gastroenterologists talk about a condition called dysbiosis in which the microflora of the intestine is not in balance or is disturbed. This can arise from antibiotic use, exposure to toxins, dietary indiscretion or insufficient dietary fibre. But it can also be influenced by stress, lack of sleep, lack of exercise, rushed eating and a whole host of medications. The antibiotics may be found in our foods – such as dairy and meat/poultry/fish products from agricultural use.
Today we want to give an overview of the gut microflora, a vital component of our physical and mental health. It is a field that has opened up enormously in the last 20 years as cheaper techniques have been developed to study this vast array of micro-organisms.
The first scientific evidence that microorganisms were part of the normal human system emerged in the mid-1880s when Austrian paediatrician Theodor Escherich observed a bacteria (later named Escherichia coli) in the intestines of children.
In the past most people thought gut bacteria were just a nuisance or were frankly harmful and better eliminated. It turns out that our bodies are made up of around 10 trillion human cells – blood, bone, muscle, nerve, liver, lung, skin – you name all the different tissues of the body.
However, our body is coated inside and out, and even within almost every cell in the body, with between 40 and 200 trillion micro-organisms – including bacteria, fungi, archaea, protozoa and viruses.
A small percentage of these are harmful, but the vast majority perform vital beneficial functions in our body. It is estimated that 60% of the dry mass of our stools is made up of micro-organisms.
Most of the microbiome inhabits the large colon. The quality of our stools is a good barometer of gut health. If we suffer from constipation, or diarrhoea, or bloating we may well have an unhealthy gut microflora. Of course there may also be numerous other causes – such as polyps and cancers, which can cause changes in our normal bowel habits, and may need investigation. But many people have been suffering with these symptoms for years.
Typically on being questioned about dietary habits, they eat predominantly refined or processed foods and plenty of animal proteins in the form of red meat and dairy, white bread and pastries, sugary drinks, and relatively little fruit, vegetables, legumes and whole grains.
Why would the diet have such a profound effect on bowel function? Next week we will present really interesting information about how to care for our microbiome to ensure that it functions optimally. In this way we will also be benefiting from the symbiotic relationship we have with this “animal” that lives within us.
Just to pique your interest, 70% of our immune system is associated with our GIT when we consider such organs as the tonsils, the Peyer’s patches of the intestine; mesenteric lymph nodes, the liver and appendix. Within the sub-epithelial layer are a host of neutrophils, eosinophils, phagocytic macrophages and T-cells which secrete numerous factors such as interleukins, tissue necrosis factors, etc., which are recruited to fight against harmful organisms. The process is highly complex, particularly in the ability of the immune system to tolerate health-promoting bacteria, but recognise and destroy harmful bacteria or organisms.
Up to 90% of the serotonin within our body (the happy chemical in our brain) is produced by the bacteria in our gut.
Many people say that this cannot be transmitted directly to the brain, except through its precursor 5HT because of the blood/brain barrier. However there has been some recent evidence to suggest that there are nerve endings within the lumen of the gut which can pick up these neurotransmitters and transport them directly to the brain. Another fascinating fact is that the gut has 5 times more nerves than the spinal cord – 500 million to be exact. In fact the gut has been called the second brain.
Makes you think / digest – which is it?
Until next time.
Dave Glass
Dr David Glass graduated from UCT in 1975. He spent the next 12 years working at a mission hospital in Lesotho, where much of his work involved health education and interventions to improve health, aside from the normal busy clinical work of an under-resourced mission hospital.
He returned to UCT in 1990 to specialise in obstetrics/gynaecology and then moved to the South Coast where he had the privilege of, amongst other things, ushering 7000 babies into the world. He no longer delivers babies but is still very clinically active in gynaecology.
An old passion, preventive health care, has now replaced the obstetrics side of his work. He is eager to share insights he has gathered over the years on how to prevent and reverse so many of the modern scourges of lifestyle – obesity, diabetes, ischaemic heart disease, high blood pressure, arthritis, common cancers, etc.
He is a family man, with a supportive wife, and two grown children, and four beautiful grandchildren. His hobbies include walking, cycling, vegetable gardening, bird-watching, travelling and writing. He is active in community health outreach and deeply involved in church activities. He enjoys teaching and sharing information.
