Dr Dingle's Blog / PPI
The intestinal microbiome is a plastic ecosystem that is shaped by environmental and genetic factors, interacting with virtually all of our organs, tissues and cells. One of the most important factors in regulating and controlling our microbiome is the pH or acid level.
While often mentioned in terms of the stomach the pH has a controlling role to play in the health of the whole GI tract from the mouth to the anus and changes in the “normal” pH anywhere in the gut can have large implications on the rest of the GI tract. The pH scale goes from 1 being very acidic to 14 being very alkaline. The level in our blood and tissues should be constantly around 7.36, neutral and the level in our GI trace varies from 1 to 8. We cover this a lot more in our book “Overcoming Illness” which focuses on the role of inflammation, oxidation and acidosis in illness.
After initial breakdown by chewing, food is churned by the smooth muscles of the stomach and is broken down by hydrochloric acid and stomach juices (enzymes). The pH of the stomach is highly acidic, around 1.5 (1.0-2.5) due to the hydrochloric acid which helps to kill harmful microorganisms, denature protein for digestion, and help create favorable conditions for the enzymes in the stomach juices such as pepsinogen. Not to mention sending messages along the GI tract that everything is working well in the stomach. If the pH is too high, say 3 or 4 (more alkaline) then the system does not work and you end up with digestive and health complications. For example, premature infants have less acidic stomachs (pH more than 4) and as a result are susceptible to increased gut infections. Similarly, the elderly show relatively low stomach acidity and a large number of people, more than 30%, over the age of 60 have very little or no Hydrochloric Acid in their stomachs.
Similarly, in gastric bypass weight loss surgery, roughly 60 percent of the stomach is removed. A consequence of this procedure is an increase in gastric pH levels that range from 5.7 to 6.8 (not 1.5) to making it more alkaline and as a result are more likely to experience microbial overgrowth. We see similar patterns in other clinical cases such as acid reflux in which treatment involves the use of proton-pump inhibitors and celiac disease where delayed gastric emptying is associated with reduced acidity and increased disease.
Unfortunately, acid reflux is often wrongly treated as a condition which involves the production of too much acid. It is in fact, the stomach finding it difficult to digest the foods, most commonly as a result not having enough acid to complete digestion and why medications (see later) which further reduce stomach acid have serious and deadly side effects on health, the digestive process and the gut microbiota. Acid reflux affects about 20% of the adult population and is much higher in older people which is consistent with the studies showing lower stomach acid as we age.
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Arguable the biggest health problem facing us today is gut health rivaling the current obesity crisis and tobacco smoking in its impact on our health. Every health condition is linked to gut health and gut healing either directly or indirectly through inflammation and oxidation. Historically every culture understood this and were involved in extensive practices of gut healing and even our own up until 60 or so years ago. The first thing health practitioners throughout history would do is to start to fix the gut.
Until recently the positive effects of the gut microbiome on our digestive system and health has been severely under rated. Wisdom of Chinese doctors from centuries ago, who somehow knew that the intestines were not merely a digestive organ, but the centre of health and wellbeing. Hippocrates was recorded as saying that all illness begins in the gut. Throughout history from the Egyptians till around 80 years ago medicine and the bowels were frequently mentioned in the same sentence and good health revolved around gut health.
Even today the nomadic Maasai tribes in Africa attribute most illnesses to the effect of “pollutants” that block or inhibit digestion. In these communities the plants are used to cure diseases served mainly as strong purgatives and emetics; they "cleanse" the body and digestive system from polluting substances.
With thousands of studies released each year the gut is known to play a major role in many health conditions including mental health issues, cardiovascular disease, allergies and asthma, autoimmune diseases, some cancers and even diabetes and weight gain. Many of these conditions which are now reaching epidemic proportions have been linked to a dysfunctional gut. Studies have shown a strong link between mental health issues including depression and what is called the gut brain axis. We also know the gut is the centre of our immune system and is strongly influenced by the gut microbiome. As a result the gut has a strong link with allergies and asthma. Peanut allergies for example are not caused by peanuts they are brought about by a dysfunctional gut microbiome.
Antibiotics and many gut medications used for controlling acid reflux have been shown to be devastating to gut health a healthy gut microbiome, as well as many of the chemicals we use around the homes and even the personal care products we apply to our skin. Even our activities either promote gut health and gut healing or harm it. Stress sends messages to the opportunistic (bad) microorganisms in the gut to tell them to start to take over from the good ones. Exercise promotes gut health and healing while no exercise or too much exercise does the exact opposite.
Fortunately, in animal studies we know that many of these conditions can be improved and even reversed if the gut microbiome is repaired. 50% of Parkinson’s Disease has been directly linked with poor gut health while improving the gut microbiome has been shown to dramatically improve symptoms.
The research also shows that while probiotics can be useful in gut healing, repairing the gut microbiome requires an understanding of what encourages a healthy gut microbiome in our diet and lifestyle as well as what causes a dysfunctional microbiome. We now know that all the healthy foods we eat, the vegetables, nuts, seeds, herbs, spices and fruit all feed the gut microbiome which then feeds us and looks after our health. All the studies on healthy diets from the Mediterranean to the original Japanese or the low inflammatory diet (DII) benefit us because they work through the gut to promote gut health and subsequently our health.