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More Evidence to Support the Theory That GERD Is Caused by Bacterial Overgrowth


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Note: this is the third article in a series about heartburn and GERD. If you haven’t done so already, you’ll want to read Part I and Part II before reading this article.

Right after publishing yesterday’s article (The hidden causes of heartburn and GERD), I came across a new research (PDF) study hot off the presses that adds support to the theory that GERD is caused in part by bacterial overgrowth. Before moving on to my next planned article in the series, I want to take some time to review this study and discuss its implications.

Malekzadeh & Moghaddam performed a retrospective study to investigate the prevalence of GERD in patients with IBS and vice versa. The data comes from a very large number of patients (6,476). To my knowledge it’s the largest data set that has been reported about the overlap between GERD and IBS.

The authors found that 64% of IBS subjects studied also had GERD, whereas 34% of the GERD patients also had IBS. They also found that the prevalence of all functional symptoms (such as nausea, changes in bowel movement, headache, etc.) was higher in overlapping GERD and IBS subjects than the prevalence in GERD subjects without IBS or IBS subjects without GERD.

Implications of the Connection between GERD and IBS

What this correspondence suggests, of course, is exactly what I argued in the last article: that IBS and GERD may very well share a common etiology and underlying mechanism. From the conclusion:

This finding shows that in overlapping GERD and IBS, other functional abnormalities of the GI tract are also highly prevalent, suggesting a common underlying dysfunction.

The authors even speculate that the underlying cause may be an overgrowth of bacteria. Specifically, they mention H. pylori as a possible culprit. I think they’re on to something!

Assessing the role of H. pylori infection in GERD and IBS patients could be a target of future research, as in the present study the prevalence of H. pylori infection in GERD patients was found to be greater than in non- GERD patients.

The Role of H. Pylori in GERD

I believe that H. pylori infection plays a significant role in the pathogenesis of GERD and other digestive disorders.

H. pylori is the most common chronic bacterial pathogen in humans. Statistics indicate that more than 50% of the world population is infected. Infection rates increase with age. In general, the prevalence of infection raises 1% with every year of life. So we can expect that approximately 80% of 80 year-olds are infected with H. pylori.

Second, we know that H. pylori suppresses stomach acid secretion. In fact, this is how it survives in the hostile acidic environment of the stomach, which would ordinarily kill all bacteria. Treating an asymptomatic H. pylori infection with antibiotics increases stomach acidity and eradicating H. pylori with antibiotics improves nearly all patients suffering from hypochlorhydria.

Although it is commonly assumed that stomach acid production declines with age, recent studies suggest that the secretion of stomach acid doesn’t decrease with age and that the trend is actually to increase, especially in men.

However, this tendency for acid secretion to increase with age is completely nullified by the corresponding increase in H. pylori infection. Since the incidence of H. pylori infection increases with age, it follows that hypochlorhydria also increases with age.

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Acid Suppressing Drugs Increase Risk of H. Pylori Infection

Perhaps most importantly for those taking acid suppressing drugs, researchers now believe that the initial infection with H. pylori can only take place when the acidity level in the stomach is decreased (albeit on a temporary basis). In two human inoculation experiments, infection could not be established unless the pH of the stomach was raised by use of histamine agonists. (1, 2)

If low stomach acid is a prerequisite to H. pylori infection, we might expect acid suppressing drugs to worsen current H. pylori infections and increase rates of infection. That’s exactly what studies suggest. Prilosec and other acid suppressing drugs increase gastritis (inflammation of the stomach) and epithelial lesions in the corpus of the stomach in people infected with H. pylori.

A 1996 article published in the New England Journal of Medicine followed two groups of people who were being treated for reflux esophagitis for a period of five years. One group took Prilosec (20-40 mg/day) and the other underwent surgical repair of the LES. Among those who had documented H. pylori infections at the start of the study and who were treated with Prilosec, the rate of atrophic gastritis increased from 59 percent at the beginning of treatment to 81 percent by the end of the study. Among those who had no atrophic gastritis at the beginning of the study, 30 percent of those who took Prilosec later developed it. By contrast, just 4 percent of the surgically treated group developed atrophic gastritis.

Another Vicious Cycle You’d Be Smart to Avoid

The connection between low stomach acid, h. pylori and acid suppressing drugs kicks off another nasty vicious cycle, similar to the one we discussed in the previous article.

Low stomach acid >>> heartburn >>> acid suppressing drugs >>> H. pylori infection >>> further reduction of stomach acid >>> chronic heartburn & GERD

The increased risk of H. pylori infection caused by acid suppressing drugs is especially significant because H. pylori infection is associated with a small but significant increase in the risk of stomach cancer.

I’ll have more to say about this in the next article.

As I mentioned in the last article, fermentation of malabsorbed carbohydrates produces hydrogen gas in the intestines. Hydrogen gas is the preferred energy source for H. pylori. Elevated levels of hydrogen gas are also associated with other nasty bugs such as Salmonella, E. coli and Campylobacter jejuni, the leading cause of bacterial human diarrhea illnesses in the world.

Excessive fructose, certain types of fiber and starch, and particularly wheat increase hydrogen production, and thus increase the risk of infection by H. pylori and other pathogenic bacteria. If you’d like to avoid heartburn, GERD and the many other unpleasant symptoms associated with bacterial overgrowth, it follows that you should minimize your intake of sugars, starches and grains.

In the next article we’ll examine the many important roles of stomach acid and the significant risks of long term hypochlorhydria.

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Join the conversation

  1. I have had H.Pylori for many years and have gone back and forth whether it should be treated or not as I have no stomach symptoms.

    However, I was bitten by a tick 5 years ago and contracted Lyme disease, then— because it took me so long to find out why I was sick (1.5 years) having this bad infection I became autoimmune with Sjogrens. It took several difficult years to beat Lyme.

    Because I’ve read that H.Pylori can lead to autoimmunity I wanted to get rid of it. I have tried every natural method I could find— some multiple times… Matula tea… colloidal silver… cabbage juicing…coptis… high quality Mastic twice a day for 2 months, then for 4 months and finally three pac antibiotic treatment. STILL POSITIVE!!
    My new Gastro says the 3 pac treatment is old and there’s a different antibiotic treatment that’s more effective. Has anyone gotten rid of this??

  2. In 2013 I woke with a burning sensation in the front of my chest. I found Chris’s articles on GERD. I went to a doctor who diagnosed gastric reflux and prescribed a proton pump inhibiter. I began taking betaine hydrochloride instead, settling on 5g with each meal. I had no gastric problems until mid-2016, when I began having mild symptoms – acid burps, a sense of fullness in in the stomach, abdominal pain and slow transit times. These symptoms gradually increased. I tried increasing betaine hydrochloride to 10g per meal, but this did not improve symptoms and I backed off to 6g. On 6th September 2017, I woke with an acid burning sensation in my throat and could not breathe for about 20 seconds. I put a foam wedge on my bed, which raised my head 150 mm. I had no further severe incidents.
    On 3rd December I checked my salt intake. My target salt intake has, for several years, been 3 teaspoons per day, primarily to counter Orthostatic Intolerance. However, I had slowly backed off and it was now only 2 teaspoons. I increased my salt intake back to 3 teaspoons. Within a week, my gastric symptoms had disappeared. On 17th December I ceased taking betaine hydrochloride.
    While I am delighted at having a properly operating digestive system again, I am puzzled about how such a small change in salt intake could have such a dramatic effect.
    I am 70 years old. Due to multiple food intolerances, my diet consists almost entirely of fish, lamb, chicken, beef tallow and vitamin and mineral supplements. My health and fitness are above my age average.

  3. Hi, I am suffering from h pylori gastritis since last 5-6 years. Never used to do exercise regularly and used to have beer, alcohol spicy and oily foods at regular interval.. used to have relapses of heartburn, stomach cramps and indigestion with bloating very often . Got my endoscopy done in 2012 and 2017 January. both resulted in gastroduodinitis with h pylori positive. Took matula herbal tea in 2012 got relief and then relapse after one year. Now I have GERD and o esophagitis symptoms too. My Gastro asked me to be on omeprazole 40 MG and sucralfate three times a day. I have started exercising and stopped alcohol, wheat and dairy since 4 weeks.. took some supplements like omega 3 but still no relief..
    Can anyone help me to heal

  4. I just happened upon your article here. I had suffered for many years with “stomach issues”. Diagnosed with IBS as a baby, ulcer as a teen, GERD as a young adult, and then adding gastroparesis shortly thereafter. Many endoscopies and a few with dilutions, 25 years of alternating PPI meds. One day on a hunch after a conversation with a friend I decided to have my primary Dr to a food allergy test at 49 years old. I’d never had one done before. I found out I was allergic to dairy, wheat, beef, pork, peanuts. I will tell you that I tried, really tried to stop taking the prescribed PPIs many unsuccessfully. I would always end up in so much pain without them. Once I stopped the foods I am allergic to, I not only have stopped the PPIs but I no longer have the stomach issues I suffered throughout my life. So kudos to what your article…you are on track.

  5. I have acid reflux and gastritis, my question is does gastritis manifest as acid reflux symptoms? And how do you tell if you have low or high stomach acid?

  6. Hi,
    I think I have gerd. I have had the following symptoms a slight difficulty in swallowing it feels like there is something in my throat, I have been coughing trying to clear my throat and belching all evening which is really tiring, which in turn creates a slight burning with the reflux, my stomach was gurgling all the time.

    After reading about low stomach acid I am now having a cup of
    honey and cider vinegar in warm water first thing in the morning and
    have upped my intake of honey during the day as honey apparently
    has hyaluronic acid which is good for gut health.

    The outcome of this is, I no longer have the acid reflux. It is lovely not to have a gurgling stomach or belching all evening, I real feel it has improved all symptoms.

  7. I dosed with 1 to 3 tablespoons each of olive oil and coconut oil far about a week to rid myself of a bacterial infection that was causing farty burps.
    I had this condition for about nine months. In the last 10 months I had one relapse and treated again and have not had any others.
    I have low stomach acid and supplement with HCI with pepsin and other digestive enzymes .
    Remember you were not what you eat , you are what you can absorb.

  8. I’ve been on and off two week cycles of omeprazole for a many, many years now for the standard reflux symptoms. I’ve even had to go on high-doses of B12 to fix anemia caused by reducing stomach acid.

    I’ve a new primary doctor now and during my last check-up, I mentioned that I thought that I had rosacea. She agreed. But, rather than prescribing the standard topical abx type creams, she said that her reading had led her to believe that rosacea was caused by low-stomach acid.

    She asked that I mix grated fresh ginger, lemon juice and salt in a glass jar and take a teaspoon every evening before dinner. I started to do just that and within days my skin was less red and the tiny pustules were drying. Within two weeks, the roughness was much smoother, too.

    Then I had to go out of town for a couple of weeks. My son had been hospitalized. I didn’t feel like messing with making up the ginger mix in a hotel. My skin flared back up again. When I got home last week, I restarted the ginger mix and my skin is again clearing up.

    I’ve been looking at research papers and I am amazed at the clinical research that indicates that bacterial infections (Helicobacter pylori specifically), low-stomach acid and rosacea go hand-in-hand. One doesn’t apparently even need bacterial overgrowth to experience extraintestinal manifestations of H. pylori – the toxins it produces is enough.

    • Dear Dianne, I just wanted to share an experience. I used to search a lot about the reflux disease, but when I consulted the doctors, they told me this kind of searching may be misleading when you do not have medical information. Please consult a doctor along with your searches.