By Wayne Persky |
A normal stomach acid level is required for healthy digestion. The pH level in the stomach of healthy individuals typically ranges between 1.0 and 2.0. The pH scale ranges from zero on the low end (highly acidic), to 14.0 on the high-end (highly alkaline). The neutral level at which a substance is neither acidic nor alkaline, is 7.0. The medical term used to describe the condition of sub-normal production of stomach acid is hypochlorhydria. And the medical term used to describe the condition of above normal production of stomach acid is hyperchlorhydria.
Note that hypochlorhydria does not necessarily imply a consistently high pH level.
The term hypochlorhydria refers to compromised acid production, regardless of the pH level in the stomach at any given time. And accordingly, the term hyperchlorhydria refers to excess acid production, regardless of the actual pH levels in the stomach at any given time. In general, these two terms refer to the production of hydrochloric acid (HCL), relative to what's considered normal, and this association is reflected in the names chosen for these terms.
Stomach acid is also known as gastric juice.
An adequate level of gastric juice is necessary for the proper digestion and absorption of proteins, minerals (including magnesium, phosphorus, calcium, zinc, copper, and iron), and vitamin B-12, and it's also important for killing bacteria and parasites that might happen to be in our food. Gastric juice is a mixture of water, mucus, HCL, pepsin, and intrinsic factor (Heda, Toro, and Tombazzi, 2022, May 8).1
Gastric juice production involves a series of integrated processes.
Although we usually visualize the production of gastric juice as a simple, straightforward process, it's actually rather complex, involving a number of steps. As noted in the Merck manual, the thought, smell, or taste of food causes the brain to stimulate the G cells located in the antrum (lower one third) of the stomach, by way of the vagus nerve (Vakil, 2021, June).2 Although most of the G cells are located in the antrum of the stomach, some are also present in the duodenum and the pancreas. The G cells secrete gastrin, and when protein actually enters the stomach, additional gastrin is secreted. Gastrin triggers the release of histamine from enterochromaffin-like cells in the stomach. The histamine attaches to the H2 receptors of the parietal cells located in the upper two thirds of the stomach, prompting the parietal cells to secrete HCL.
GERD is the result of a weak esophageal sphincter.
The lower esopahgeal sphincter prevents reflux of the acidic stomach contents back into the esophagus. The more acidic the stomach contents, the tighter it clenches. If there is low acid, it doesn’t clench as tightly, and there is more chance of reflux. Note that if we have reflux or GERD issues, normal, and even relatively high pH (weak stomach acid) concentrations are still sufficient to cause damage to our esophagus (when acid is refluxed). Highly acidic stomach acid obviously can cause much worse damage. But normally (for those of us who don't have GERD), high stomach acid, in otherwise healthy individuals, should not cause any problems, because the more acidic the stomach contents (the lower the pH level of the stomach acid), the tighter the lower esophageal sphincter will clinch, thereby preventing any acid reflux problems.
Doctors and patients alike typically misinterpret the symptoms.
Typically, acid reflux, or GERD, is a symptom of sub-normal stomach acidity. And that condition is usually due to one of three possibilities:
- Physical damage to the lower esophageal sphincter or the stomach , due to surgery, disease, or other trauma.
- Use of proton pump inhibitors (PPIs), or excessive use of H2 blockers or antacids
- Aging — as we get older, our ability to produce normal amounts of stomach acid tends to decline
So when patients complains of reflux, why do doctors almost always assume excess acid, and prescribe a PPI?
While it's true that the symptoms of abnormally high stomach acid production are virtually identical to the symptoms of abnormally low stomach acid production, the fact that a condition of high stomach acid is uncommon, and rarely causes problems, should provide a rather strong guiding light for any medical professional, when a patient complains of reflux problems. The problem is almost always low stomach acid — not high stomach acid. Tests that involve swallowing various types of capsules to accurately measure the pH of stomach acid are readily available, but they are rarely used.
When you hear hoofbeats, think horses, not zebras.
In medical school, students pursuing a medical degree are traditionally taught that, “when you hear hoofbeats, you should expect to see horses, not zebras”, and following that old rule usually works well for practicing doctors, because they rarely, if ever, see rare diseases in their practice. So why would they expect to see zebras in this case?
Doctors seem to view PPIs as a one-size-fits-all, handy dandy solution.
Could the problem be due to the fact that PPIs are a quick, easy, although temporary, fix, that allow the doctor to quickly send patients on their way, happily clutching a prescription that they believe will resolve their problem? This fits right in with the current assembly line healthcare policies. And this practice is so popular that the annual value of the sale of PPIs amounts to many billions of dollars. By comparison, the most common treatment for low stomach acid is betaine HCL, which is available over the counter for a paltry sum, and it's annual sales volume is so low that it's doubtful that the annual sales value is even known. Doctors are trained to write prescriptions, so that's what they do, even when the prescription turns out to be for an iatrogenic drug such as a PPI. PPIs actually weaken the lower esophageal sphincter, thereby causing the very symptoms they are prescribed to treat (Duman et al. (2011).3
What causes hypochlorhydria?
Atrophic gastritis is a chronic inflammation and thinning of the lining of the stomach, and it causes hypochlorhydria. Decades ago, a study showed that the prevalence of atrophic gastritis in subjects over the age of 60 was approximately 30%. According to an online article by Long Island Spine Specialists (n.d.), approximately 22% of the US population are estimated to have hypochlorhydria.4, 5 Furthermore, they list 10 common symptoms of low stomach acid.
- Heartburn
- Difficulty digesting meat properly
- Gas and bloating after meals
- Food allergies and intolerances
- Nutritional deficiencies
- Skin problems (acne)
- Leaky gut syndrome
- Undigested food in stools
- Hair loss (in women)
- Diarrhea or constipation
They also note a couple of additional causes of low stomach acid, stress and excessive sugar intake:
- Stress
- Aging
- Stomach surgery
- Medications
- Excessive sugar intake
This sounds like a description of MC.
Interestingly, not only are many of those symptoms reminiscent of microscopic colitis (MC), but so are most of the causes. Is MC associated with low stomach acid? A search of the literature suggests that the possibility has never been researched. Note, however, the existence of many research articles describing the association of MC and the use of PPIs. PPIs are prescribed specifically to decrease the acidity level in the stomach (raise the pH level). The article noted above also points out that research shows that 40% of individuals who have acne, also have low stomach acidity (Long Island Spine Specialists. (n.d.). But low stomach acid is also notorious for causing psoriasis, eczema, and other skin problems, all of which are rather common issues for many MC patients
This appears to be a “which comes first, the chicken or the egg”situation.
Does low stomach acid increase the risk of developing MC? Logically, it probably does, because poor digestion can cause the nutritional deficiencies and leaky gut syndrome that increase the risk of developing MC. Does MC cause low stomach acid? Considering the symptoms typically associated with MC, such as acid reflux or GERD, disbyosis, and many others, if low stomach acid doesn't already exist, MC will probably cause it to develop.
What can we do to resolve a low stomach acid problem?
Reiterating the most common causes of low stomach acid (in alphabetical order, not necessarily in the order of prevalence), and adding a sixth item to the list, zinc deficiency, as suggested by Eske, (2020, July 29).6
- Aging
- Excessive sugar intake
- Medications
- Stomach surgery
- Stress
- Zinc deficiency
1. Aging is a natural process that inevitably occurs.
But as it occurs, we need to be aware of the fact that as we grow older, the possibility that our stomach acid production may decline, becomes more likely, and we may need to adopt a plan that will offset a reduction, if it occurs, by supplementing with betaine HCL, or adopting some of the dietary practices suggested by the Cleveland Clinic (2022, June 27). Note that the Clinic points out that adopting some or all of these diet changes won't resolve hypochlorhydria, but it may help to improve digestion.
- Eating protein at the beginning of a meal helps to stimulate acid production
- Waiting to drink fluids at least 30 minutes after finishing a meal allows our stomach more time to produce acid and metabolize proteins
- They suggest eating probiotic foods such as yogurt, miso, and sauerkraut to help boost good gut bacteria, which should help to minimize bad bacteria
- Very fatty foods and processed foods should be avoided, because they're difficult to digest
- Eating smaller meals, and chewing thoroughly, will enhance digestion
- Finishishing eating at least two or three hours before bedtime, will allow time for digestion before going to bed
- And they point out that anyone following a vegetarian diet will need to supplement protein, iron, calcium, and vitamin B12
Many of us already follow some or most of those guidelines.
2. Both excessive sugar intake and stress can lead to leaky gut.
And leaky gut can cause low stomach acid, along with various other digestive problems. In these cases, reducing sugar intake significantly, and lowering chronic stress levels may be necessary in order to restore gut barrier integrity. But leaky gut is also associated with IBD's, including MC. And whenever that's the case, achieving remission of the IBD is usually necessary in order to resolve the leaky gut issue, which may resolve the low stomach acid problem. However, for older IBD patients, putting the disease into remission may not always resolve the low stomach acid problem, especially when chronic gastritis is present. Further treatment, such as the use of betaine HCL may be necessary.
3. Only a few kinds of medications tend to cause low stomach acid.
Although chronic use of ordinary antacids or H2 receptor blockers can cause low stomach acid, by far, the most common cause of low stomach acid is taking a PPI. PPIs have FDA approval only for short-term use. And yet many doctors ignore that limitation. Obviously, if the problem is due to a medication, such as a PPI, weaning off the drug, and discontinuing the treatment will be necessary in order to resolve a low stomach acid problem.
4. Stomach surgery can interfere with acid production.
Surgery of the stomach can have unintended consequences, such as compromised gastric acid production. In such cases supplemental remedies may be necessary, depending upon the extent of the problem
5. Stress can have a major effect on stomach acid production.
Although some authorities claim that stress increases gastric acid levels, published research shows that stress actually reduces the production of stomach acid (Esplugues, et al., 1996).7 Those claiming that stress increases the production of stomach acid are probably confused by the fact that stress increases reflux and GERD problems, and it's well established, as we've already seen, that reflux and GERD problems are increased as stomach acidity is reduced, because reduced stomach acid levels cause the lower esophageal sphincter to clamp shut less securely, allowing it to leak stomach contents back into the esophagus, sporadically.
6. Zinc is used by the stomach when producing HCl.
- oysters
- lobster
- beef
- nuts and seed cashews [sic]
- beans
- yogurt
- fortified breakfast cereal
Betaine HCl seems to be the most popular treatment for patients with low stomach acid.
For those who want to try betaine HCl, Guilliams and Drake, (2020), have suggested a carefully laid out procedure for determining the proper dose of betaine Hcl.8 Following a well defined protocol such as this for determining a personal betaine HCl dose is highly recommended.
Please don't confuse the issue of low stomach acid with BAM.
The diarrhea problem caused by bile acid malabsorption (BAM) is a completely different issue. During digestion, the gallbladder tends to release more bile (to help digest fats in the diet) than we need for normal digestion, and it releases the bile in the ileum (just below the stomach). The excess bile is normally reabsorbed in the terminal ileum (the lower section of the ileum just above the cecum and the colon).
But because the terminal ileum is almost always severely inflamed in MC patients when the disease is active, the terminal ileum is unable to reabsorb the excess bile, and when it's dumped into the colon it promotes diarrhea. The proper treatment for this issue as cholestyramine, which tends to sequester the excess bile so that it cannot contact the epithelia of the colon when it's dumped into the colon, thereby preventing the bile from causing diarrhea.
But because the terminal ileum is almost always severely inflamed in MC patients when the disease is active, the terminal ileum is unable to reabsorb the excess bile, and when it's dumped into the colon it promotes diarrhea. The proper treatment for this issue as cholestyramine, which tends to sequester the excess bile so that it cannot contact the epithelia of the colon when it's dumped into the colon, thereby preventing the bile from causing diarrhea.
Summarizing
Low stomach acid is a common problem. The medical term for deficient stomach acid production is hypochlorhydria, and the medical term for excess stomach acid production is hyperchlorhydria. Stomach acid, also called gastric juice ,is a mixture of water, mucus, HCL, pepsin, and intrinsic factor.
The acid source is HCL, and pepsin is the enzyme primarily used to digest protein. Adequate stomach acidity is necessary for the proper digestion of protein, minerals, vitamin B-12, and for destroying bacteria and parasites in food. Although hypochlorhydria compromises digestion, and can lead to a deficiency of vitamins and minerals, and possibly other nutrients, hyperchlorhydria seldom causes digestive problem except for patients of Zollinger-Ellison syndrome.
Although medical tests are available, most doctors don't bother to use them. Instead,they prescribe a PPI when patients come to them with symptoms typical of low stomach acid, and this practice probably makes, PPIs the primary cause of low stomach acid, although low stomach acid can be caused by at least half a dozen different issues (including aging). If the cause is known , it may indicate a preferred remedy.
The acid source is HCL, and pepsin is the enzyme primarily used to digest protein. Adequate stomach acidity is necessary for the proper digestion of protein, minerals, vitamin B-12, and for destroying bacteria and parasites in food. Although hypochlorhydria compromises digestion, and can lead to a deficiency of vitamins and minerals, and possibly other nutrients, hyperchlorhydria seldom causes digestive problem except for patients of Zollinger-Ellison syndrome.
Although medical tests are available, most doctors don't bother to use them. Instead,they prescribe a PPI when patients come to them with symptoms typical of low stomach acid, and this practice probably makes, PPIs the primary cause of low stomach acid, although low stomach acid can be caused by at least half a dozen different issues (including aging). If the cause is known , it may indicate a preferred remedy.
References
1. Heda, R., Toro, F., & Tombazzi, C.R. (2022, May 8). Physiology, Pepsin. [Web log messaage]. Retrieved from https://www.ncbi.nlm.nih.gov/books/NBK537005/
2. Vakil, N. (2021, June). Overview of Acid Secretion. Merck Manual, Professional Version, [Web log message]. Retrieved from https://www.merckmanuals.com/professional/gastrointestinal-disorders/gastritis-and-peptic-ulcer-disease/overview-of-acid-secretion
3. Duman, M., Özer, M., Reyhan, E., Demirci, Y., Atıcı, A.E., Dalgıç, T. . . . Genç, E. (2011). In vitro effect of pantoprazole on lower esophageal sphincter tone in rats. World Journal of Gastroenterology, 17(46), 5105–5109. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3235594/
4. Russell, R. M. (1997, November 26). Gastric Hypochlorhydria and Achlorhydria in Older Adults. The Journal of the American Medical Association, 278(20), 1659. Retrieved from https://jamanetwork.com/journals/jama/article-abstract/419006
5. Long Island Spine Specialists. (n.d.). 10 Telling Signs You Could Have Low Stomach Acid. [Web log message]. Retrieved from https://www.lispine.com/blog/10-telling-signs-you-could-have-low-stomach-acid/
1. Eske, J. (2020, July 29). How can you naturally increase stomach acid? [Weblog message]. Retrieved from https://www.medicalnewstoday.com/articles/how-to-increase-stomach-acid
7. Esplugues, J. V., Barrachina, M. D., Beltrán, B., Calatayud, S., Whittle, B. J. R., & Moncada, S. (1996). Inhibition of gastric acid secretion by stress: A protective reflex mediated by cerebral nitric oxide. Proceedings of the National Academy of Sciences of the United States of America, 93(25), 14839–14844. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC26223/
8. Guilliams, T. G., and Drake, L. E. (2020). Meal-Time Supplementation with Betaine HCl for Functional Hypochlorhydria: What is the Evidence? Integrative Medicine: A Clinician's Journal, 19(1), 32–36. Integrative Medicine: A Clinician's Journal, Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7238915/