August 21st, 2017 - Brian Maguire

Most people don’t realize the vital role that stomach acid (HCL) plays in digestion and overall health! Produced by the parietal cells lining the stomach, HCL is one of the main components of the stomach’s gastric juices. HCL is essential for maintaining the alkaline/acid balance needed during this phase of digestion. Ample amounts of HCL are required in order to emulsify the foods consumed, as well as to sterilize and destroy pathogens before they can reach the intestines. This acid is critical for proper absorption and assimilation of nutrients in each subsequent stage of the digestive process. As previously mentioned, the right amount of HCL is necessary for pepsin to be released to break down protein. When HCL is secreted it also alerts the liver and gallbladder to release bile for the proper breakdown of fats and signals the pancreas to release very alkaline forming bicarbonates to neutralize broken down food (chime) for safe entry into the small intestines.

There are certain, most oftentimes preventable variables, that can negatively influence HCL production. Aging (without HCL supplementation), unmanaged stress, poor dietary choices (refined carbohydrates, fried and processed foods, sodas, etc.…), overconsumption of cooked foods, and foods laden with pesticides and chemical additives, are a few of the primary factors that contribute to irregular HCL levels. Years of abuse wear out certain systems in the body, in this case its HCL production. Over-production of stomach acid due to poor diet and lifestyle habits will only last for so long. Eventually HCL production is hampered, diminishing its required volume for healthy digestion.

The under production of HCL can cause food to be retained in the stomach for long intervals (delayed emptying), leading to GERD, malnutrition, pathogenic bacterial overgrowth, blood sugar fluctuations, intestinal conditions, and just about any disease you can think of. The negative consequences of low HCL cannot be overstated!

Hydrochloric acid levels MUST be within normal pH ranges for the digestive system (and all other body systems for that matter), to perform adequately and promote disease prevention. Low HCL levels, clinically known as hypochlorhydria, is a very common issue, especially as you age. This detrimental condition affects up to half of the US population or more!

There are also other circumstances that can result in low stomach acid production.

  • Hypochlorhydria can be connected to gastroparesis, which is delayed gastric emptying. Gastroparesis can be the result of a malfunctioning vagus nerve, which compromises the function of the muscles of the stomach and intestines so that food slows down or even stops moving through the digestive tract.
  • Imbalance of magnesium, calcium, and potassium can also be the issue. Many people are deficient in these minerals, especially magnesium, which can stunt muscle contraction in the GI tract.
  • Yet another cause can be a deficiency in the minerals chloride, sodium and/or zinc, as these are needed to produce sufficient HCL.
  • Other causes can be parietal cell autoimmunity where the body attacks the parietal cells that manufacture stomach acid and allow B12 to be absorbed, or as a side effect of medications like narcotic pain relievers, opiates, and proton pump inhibitors.
  • Pylori bacteria can infect the lining of the stomach or upper small intestine, which over time leads to ulcerations. H. Pylori can be the cause of and/or the effect of low stomach acid. These insidious bacteria protect themselves from the acids of the stomach by secreting alkaline substances and are said to effect over half the population.
  • Very low salt diets can also be an issue. Chloride is a major component of stomach acid.

The stomach must maintain a very acidic environment throughout this phase of the digestive process as many citations convey.

Research and studies have shown that when HCL levels are unfavorably low, stomach pH levels can increase to over 4.0, reducing the system’s bactericidal effect, or ability to kill pathogenic microbes from ingested substances. (Martin Sen et al. 2005, Giannella et al. 1972, Wilder-Smith et al. 1992, Giannella et al. 1972, Waldum,1995).

The under production of HCL can cause food to be retained in the stomach for long intervals, leading to malnutrition, bacterial overgrowth, and blood sugar fluctuations. Without sufficient HCL, not only are enzymes rendered inactive, but calcium, magnesium, iron, zinc, vitamin B12, folic acid, proteins, and other nutrients are not properly assimilated and absorbed (Cater et al. 1992, Lotz et al. 1968, Russell 1987).

Besides nutrient deficiencies, individuals with low levels of HCL are much more likely to develop illness from bacterial pathogens like E. coli, H. Pylori, ulcers, as well as stomach cancer (Sarker et al. 1992, Cave et al. 1989, Cater 1992).

Minerals have various pH levels at which they can be assimilated into the body. Minerals on the lower end of the atomic scale can be assimilated in a wider pH range, as opposed to minerals higher up on that scale requiring a tighter pH range to be utilized efficiently. For instance, sodium and magnesium assimilate in a broader pH range, while this range reduces somewhat for calcium and potassium, then more so for manganese and iron, even more for zinc and copper, then very tight for iodine.

Iodine, which is high up on the atomic scale, requires near perfect pH for its assimilation into the body. Many issues can arise when this mineral is lacking in our diets or not absorbed. Besides sodium chloride, iodide is also needed for the production of stomach acid. It has been proven that iodine deficiency can lead to fibroids, fibrocystic breast disease, ovarian cysts, and makes you more susceptible to reproductive cancers. Iodine, as you may know, is one of the most important minerals for proper functioning of thyroid. But, the thyroid can’t access too much iodine unless the gastrointestinal pH is near perfect.

With society as a whole being in a pH imbalanced, inflammatory, toxic state, one would suspect a great deal of thyroid issues. As a matter of fact, it is estimated that 60 million Americans fall outside the thyroid-stimulating hormone reference range, and thus could conceivably be diagnosed with thyroid disease! Malfunctioning thyroids have been connected to fatigue, weight gain, depression, arthritis, heart attacks, diabetes, and cancer, and yes, iodine deficiency can have a lot to do with it since iodine feeds the thyroid. Halogens like fluorine (F), chlorine (Cl), bromine (Br) found in the food supply and water can also negatively impact thyroid function by binding to thyroid receptor sites preventing the binding of much needed iodine.


Low HCL production can also initiate another agonizing predicament that involves the alteration of the muscle tone of the lower esophageal sphincter (LES). The LES is a muscle at the end of the esophagus that meets the upper part of the stomach and functions as a valve, preventing acid and stomach contents from traveling up from the stomach. The LES is supposed to close after you eat, but when HCL is lacking it can remain open, allowing for a backflow of stomach content.

In order to relieve uncomfortable symptoms caused by abnormal HCL production, you may reach for antacids. You are most likely under the impression that the symptoms of heartburn, indigestion, and gastroesophageal reflux disease (GERD) result from the over-production of stomach acid. You very mistakenly may believe that you are overproducing stomach acid when in actuality you are not producing enough. When you are young, stomach acid production is at its peak, however, as you age, in conjunction with many years of consuming cooked, and processed foods, HCL production diminishes. Without adequate HCL, food cannot be broken down, resulting in lactic acid fermentation, which does a very poor job processing the food. Not only does this lead to indigestion and malabsorption, but the gases produced by the fermentation can force the LES open causing acid reflux. So, you can see how low stomach acid production can be the culprit.

Most likely you have been bombarded by ads for over-the-counter or prescription antacids and acid-suppressing drugs, and even more dangerous proton pump inhibitors. They claim to buffer acids in the stomach and ease the pain associated with these conditions. Their claim to reduce stomach acid may be valid, but is that what you want or need? In reality, it is much more likely that your symptoms are caused by the ABSENCE of HCL, not too much!. One thing to be aware of is that antacids do not heal any underlying conditions. Conversely, they can and do create further damage. They neutralize what little stomach acid remains, leaving food undigested; causing bloating, gas, indigestion, and malnourishment (Greenbaum 1999). The body is NEVER deficient in antacids, but you do need adequate amounts of HCL or you will not be able to digest your food!

As you know, stomach pH levels need to remain LOW during the digestive process. However, when you take antacids, pH levels in the stomach become elevated or more alkaline. When this happens, the pyloric sphincter can become impaired, creating a disastrous situation! The pyloric sphincter is a muscle in the lower part of the stomach that acts as a valve controlling the flow of partially digested material from the stomach into the duodenum for further digestion. This valve then prevents regurgitation of food from the intestine back into the stomach. So when there is insufficient HCL the pyloric sphincter can open, releasing partially digested, overly acidic food, into the small intestine prematurely.

This is a fairly common problem and many people are not even aware they have it. Malfunctioning of this valve includes spasms that prevent it from opening or closing completely. When the pyloric valve spasms, it gets inflamed, causing bloating then very sharp, sometimes excruciating pain can ensue as food tries passing from your stomach into the small intestine. If the spasms intensify, nausea and even violent vomiting can result as your stomach tries to release its contents. When the pyloric valve doesn’t close properly, bile can then flow back into the stomach from the intestines. Bile reflux and acid reflux have many similarities and can be very hard to differentiate. The two conditions can happen simultaneously as well. Bile reflux can cause some SERIOUS damage to the stomach and esophageal linings, leading to bleeding ulcers and greatly increases your risk of developing esophageal cancer!

The importance of adequate HCL production CANNOT be overstated for both digestive pH balance and overall health. Inadequate production of this vital acid can manifest a plethora of complications throughout the body. HCL imbalances affect all the mechanics of the intestinal track (LES and pyloric sphincter), deterring crucial nutrient absorption and assimilation, initiating various symptoms and conditions, and throwing off pH levels throughout the body. Thus, hydrochloric acid is a prerequisite, not only for optimal digestive pH health, but for the strength and well-being of the entire body as a whole!




Martinsen, T. C., Bergh, K., & Waldum, H. L. (2005). Gastric juice: a barrier against infectious diseases. Basic & clinical pharmacology & toxicology, 96(2), 94-102.

Giannella, R. A., S. A. Broitman & N. Zamcheck: Gastic acid barrier to ingested microorganisms in man: studies in vivo and in vitro. Gut 1972, 13, 251–256.

Wilder-Smith, C. H., C. Spirig, T. Krech & H. Merki: Bactericidal factors in gastric juice. Eur. J. Gastroenterol. Hepatol. 1992, 4, 885–891.

Giannella, R. A., S. A. Broitman & N. Zamcheck: Gastic acid barrier to ingested microorganisms in man: studies in vivo and in vitro. Gut 1972, 13, 251–256.

Waldum, H. L.: Gastrin-physiological and pathophysiological role: clinical consequences. Dig. Dis. 1995, 13, 25–38

(Martinsen et al. 2005, Giannella et al. 1972, Wilder-Smith et al. 1992, Giannella et al. 1972, Waldum, 1995)

Kelly GS: Hydrochloric acid: physiological functions and clinical implications. Altern Med Rev, 1997;2:116-127.

Murray MT: Indigestion, antacids, achlorhydria and H. pylori. Am J Nat Med, 1997;4:11-14, 16,17.

Greenbaum DS: Dyspepsia: relief not yet beyond belief. Am Fam Physician,1999; 60:1649,1650 & 1656.

Cater RE 2nd: The clinical importance of hypochlorhydria (a consequence of chronic helicobacter infection): its possible etiological role in mineral and amino acid malabsorption, depression, and other syndromes. Med Hypotheses, 1992;39:375-383.

Lotz M, Zisman E, Bartter FC: Evidence for a phosphorus depletion syndrome in man. N Engl J Med, 1968; 278:409.

Russell R, Golner B, Krasinski S: Effect of acid lowering agents on folic acid absorption. Fed Proc, 1987;46:1159.

Sarker SA, Gyr K: Non-immunological defense mechanisms of the gut. Gut, 1992;33:987-993.

Cave DR, Vargas M: Effect of a Campylobacter pylori protein on acid secretion by parietal cells. Lancet, 1989;2:187-189.

Cater RE 2nd: Helicobacter (aka Campylobacter) pylori as the major causal factor in chronic hypochlorhydria. Med Hypotheses, 1992;39:367-374.

Prousky, J. E., & Kerwin, C. (2002). Niacin (Nicotinic Acid) a putative treatment for hypochlorhydria: re-analysis of two case reports. Journal of orthomolecular medicine, 17(3), 163-169.

Ostrow, J. D., & Resnick, R. H. (1959). Hyperchlorhydria, duodenitis and duodenal ulcer: a clinical study of their interrelationships. Ann Intern Med, 51, 1303-1328.