June 24, 2014

Gas. Bloating. Bacterial overgrowth. Indigestion. Heart Burn.

These are just some of the signs of a stomach with low acid levels.

A faulty digestive system could be leaving protein, fat, vitamins and minerals unabsorbed, and setting you up for future infections.

Not to mention that it’s hard to be the life of the party if you’re gassy and bloated.

A lot of attention has been placed on probiotics, the good bacteria found in the intestines. There’s no doubt that the gut flora in the intestines are important. But the environment in the stomach can be equally critical to one’s ability to digest and absorb nutrients, and limit the levels of bad bacteria that colonize the digestive system.

This post will discuss the importance of maintaining normal pH levels in the stomach, what happens when things go awry, and talk about how to bring the stomach environment back to normal.


The pH of a healthy stomach is usually 1.0-2.0. This low pH level typically keeps it free of microbes. Battery acid has a pH of 1.0, so we’re talking about a really acidic environment.

One of the benefits of this highly acidic environment is that it helps keep the rest of the digestive tract more sterile. It’s difficult for pathogenic bacteria to survive in this acidic environment. If the acid level starts to fall (pH begins to rise), it can reduce the stomachs ability to kill off pathogens.[i]

Microbes begin to accumulate when the pH exceeds 4.0 and can significantly increase at a pH over 5.0.[ii]

The growth of the wrong kind of bacteria can lead to socially unpleasing flatulence, diminished vitamin and mineral absorption, bloating and even certain types of cancer.

Because the acidic environment is important for the breakdown and absorption of food, rising pH levels may limit the absorption of macro- and micronutrients.

Possibly worst of all (at least for the fitness-minded individual), this subpar ability to digest and absorb food may limit recovery from exercise and the ability to add lean mass.


People tend to produce less stomach acid as they age. This could be one of the reasons aging adults need to eat greater amounts of protein to avoid muscle or bone loss.[iii]

High volumes or intensities of exercise may also reduce the secretion of gastric acids and affect gastric function.[iv]

Other causes of low pH levels in the stomach include chronic gastritis and long-term use of histamine-2 receptor antagonists, proton pump inhibitors, and antacid therapies.[v],[vi]


Hydrochloride (HCl) should be secreted at the very beginning of a meal, or even in anticipation of the meal, to support the digestion of the food and help maintain the normal pH of the stomach.

HCl converts pepsinogen into pepsin, an enzyme that assists the breakdown of protein. It also stimulates the release of other enzymes and bile that support the digestion and absorption of carbohydrates, fats and vitamins A and E.[vii]

HCl also aids in the absorption of folic acid, ascorbic acid, beta-carotene and iron by helping them release from food and enhancing their bioavailability.[viii]

Calcium, magnesium, zinc, copper, chromium, selenium, manganese, vanadium, molybdenum and cobalt are also poorly absorbed when stomach acid levels are low.[ix]

Low stomach acid levels not only hamper digestion and absorption of food and nutrients, but it can also increase the risk of gastric cancer.[x]

Certain drugs have less of an effect when an individual’s stomach pH levels are abnormal.[xi]

Contrary to what most people think, heartburn is a symptom of insufficient stomach acid production, not excess stomach acid. Other symptoms of low stomach acid include bloating and indigestion. Unfortunately, many people take antacids which make the problem even worse.

Allergies, gallstones and asthma are also associated with impaired acid secretion.


The balance of good and bad bacteria in the digestive tract has become a popular area of interest. While probiotics provide support for the balance of good bacteria, low stomach acid levels may open the door for growth of bad bacteria, offsetting their effects.

The highly acidic environment of a healthy stomach tends to kill pathogenic bacteria, but when acid levels fall, they may make it through the stomach and colonize in the intestines.

When stomach acids are maintained in their normal pH range of 1-2, ingested E. coli is inactivated, so maintaining normal stomach acid levels can prevent this bacteria from causing health problems.

Infection by another bacteria, H. pylori, was strongly correlated with low stomach acid levels as well.[xii] H. pylori is a cause of common digestive problems such as gastric ulcer disease and gastritis.[xiii]

In an animal study, overgrowth of H. pylori led to iron deficiency. This is interesting because so many highly active females have low iron levels.[xiv] In some, supplementing with additional iron (particularly in the form of bisglycinate), can be an effective solution, but others may need to improve the environment of the stomach and/or intestines to get rid of the bacteria hampering absorption.

Another study showed that when stomach acids were low, it led to the overgrowth of Bifidobacteriaceae in the stomach, which are typically only found in the mouth and intestines, not in the stomach.[xv]

As you can imagine, the use of acid lowering medication (prescription or over-the-counter) may reduce acid levels enough to allow bacteria to grow.


Interestingly, many digestive support products are diluted with lactose, which can be problematic to those who are sensitive to lactose.[xvi] The individual raw materials may contain lactose, which may not be disclosed on a supplement label.

People may buy a supplement to assist their digestive system, and unknowingly introduce an inactive ingredient from that supplement that causes further digestive problems.

Look for a gastric support product that contains both betaine hydrochloride and pepsin as these should be taken together whenever someone is trying to improve gastric function.* The reason is that if an individual is producing insufficient acid, it’s likely he or she also produces insufficient pepsin which is important for digesting protein.*

Betaine hydrochloride is a stabilized form of hydrochloric acid and has been shown to quickly lower stomach pH levels in those with hypochlorhydria.xi*

L-glutamic hydrochloride is another stabilized form of hydrochloric acid, to further help lower pH levels.*

A comprehensive product should also contain pancreatin which includes the pancreatic enzymes, protease for protein digestion, lipase for fat digestion, and amylase for carbohydrates digestion.* Ox bile also supports the digestion of fat.*

It is recommended to take  a digestive support product at the beginning of a meal. It should not be used on an empty stomach.

Most people can start by taking two capsules at the beginning of meal, but ideal doses are very individualized.

BioGest from Thorne Research is a good, comprehensive gastric support product. It contains a blend of five ingredients to assist with digestion and help normalize the stomach environment.*

Thorne Research does not use lactose-diluted ingredients. They are pure and free of lactose.

Once an ideal, individualized dose is determined, BioGest should be taken with each meal.*The ideal dose may vary over time as a result of dietary changes, health changes, aging and other factors.*

An ideal dose may vary from meal to meal as well, if the protein content of the meals varies significantly. Dinner at Fogo De Chao may require more BioGest for proper digestion than a breakfast of a few eggs and some chicken sausage.*

BioGest is not recommended for those with ulcers, or taking medication that may irritate the lining of the stomach, such as NSAIDs.


There’s no doubt that nutrition plays an important role in our health, and that our nutrition comes from the foods we eat. However, we only gain the benefit of those nutrients if we can break down and absorb them.

The stomach plays a very important role contributing to much of the digestion, and some of the absorption of nutrients.

If the stomach does its job with the foods we eat, the intestines, and the probiotics in them, can do their job.

*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.


The posts on this blog are not intended to suggest or recommend the diagnosis, treatment, cure, or prevention of any disease, nor to substitute for medical treatment, nor to be an alternative to medical advice. The use of the suggestions and recommendations on this blog post is at the choice and risk of the reader.



[i] Monograph. Hydrochloric Acid. Alt Med Rev. 2002

[ii] Väkeväinen S, Tillonen J, Salaspuro M, Jousimies-Somer H, Nuutinen H, Färkkilä M. Hypochlorhydria induced by a proton pump inhibitor leads to intragastric microbial production of acetaldehyde from ethanol. Ailment Pharmacol Ther. 2000;14(11):1511-8

[iii] Heaney RP, Layman DK. Amount and type of protein influences bone health. Am J Clin Nutr. 2008;87(suppl):1567S-70S

[iv] Bi L, Triadafilopoulos G. Exercise and gastrointestinal function and disease: an evidence-based review of risks and benefits. Clin Gastroenterol Hepatol. 2003;1(5):345-55

[v] Kimura K, Satoh K, Saifuku K, Taniguchi Y, Hiratsuka H. Concept of specification for biopsy sites. Dig Endosc. 2001;12:217-220

[vi] Dicksved J, Lindberg M, Rosenquist M, Enroth H, Jansson JK, Engstrand L. Molecular characterization of the stomach microbiota in patients with gastric cancer and in controls. J Med Microbiol. 2009;58:509–16

[vii] Tang G, Serfaty-Lacrosniere C, Camilo ME, and Russell RM. Gastric acidity influences the blood response to a beta-carotene dose in humans. Am J Clin Nutr. 1996;64:622-626

[viii] Saltzman JR, Kemp JA, Golner BB, et al. Effect of hypochlorhydria due to omeprazole treatment or atrophic gastritis on protein bound vitamin B12 absorption. J Amer Coll Nutr 1994;13:584-591

[ix] English J. Gastric Balance: Heartburn Not Always Caused by Excess Acid. Nutrition Review. April 22 2013. Accessed April 24 2014.

[x] El-Omar, EM, Penman ID, Ardill JE, Chittajallu RS, Howie C, McColl KE. Helicobacter pylori infection and abnormalities of acid secretion in patients with duodenal ulcer disease. Gastroenterology. 1995;109:681-691

[xi] Yago MAR, Frymoyer AR, Smelick GS, Frassetto LA, Budha NR, et al. Gastric Re-acidification witih Betaine HCl in Healthy Volunteers with Rebeprazole-Induced Hypochlorhydria. Mol Pharm. 2013 Nov 4;10(11):4032-7. doi: 10.1021/mp4003738

[xii] Morihara M, Aoyagi N, Kaniwa N, Kojima S, Ogata H.Assessment of gastric acidity of Japanese subjects over the last 15 years. Biol Pharm Bull 2001 Mar;24(3):313-5.

[xiii] Young DG. A stain for demonstrating Helicobacter pylori in gastric biopsies. Biotech Histochem 2001 Jan;76(1):31-4.

[xiv] Thomson MJ, Pritchard DM, Boxall SA, Abuderman AA, Williams JM, et al. Gastric Helicobacter infection induces iron deficiency in the INS-GAS mouse. PLoS One. 2012;7(11):e50194 doi:10.1371/journal.pone.0050194

[xv] Mattarelli P, Brandi G, Calabrese C, Fornari F, Prati GM, et al. Occurrence of Bifidobacteriaceae in human hypochlorhydria stomach. Micro Eco Health Dis. 2014;25:21379

[xvi] Roxas M. The Role of Enzyme Supplementation in Digestive Disorders. Alt Med Rev. 2008;13:307-314