Causes of Acid Reflux: H. Pylori, Histamine & Ammonium

Acid reflux isn't just due to excess acid; it can also result from insufficient acid. Helicobacter pylori can modify stomach chemistry, inflame the stomach lining, alter gastrin and histamine signalling, and generate ammonium through its urease activity, even as it coexists with mechanical factors that can also cause reflux. As a functional nutritionist, I have encountered heartburn as a symptom, and this distinction is important since taking supplements haphazardly, using antacids, relying on proton pump inhibitors or following so-called "low stomach acid" protocols can interfere with accurate diagnosis and lead to a delay in proper treatment of the underlying cause.

Acid Reflux Protocol

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This health pack contains a 90-day supply of the Toxaprevent Medi Plus Sachets, which: Detoxes ammonium and histamine from the stomach Frees bicarbonate to counteract stomach acid naturally Natural, vegan, and no additives 90 day supply (90 Sachets) i.e. 1 x… read more

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Could H. pylori be driving your reflux symptoms?

Yes, H. pylori may cause upper digestive problems that resemble reflux, but it is not the only cause and does not automatically lead to heartburn. In my clinical experience, I often see cases where the test is positive, but there are no symptoms, since H. pylori is one of the commensal bacteria. It colonises the gastric mucosa, secretes urease, is able to survive in an acidic environment, and is closely associated with chronic gastritis, peptic ulcer disease, and an increased risk of gastric cancer in people who are susceptible [1,2]. The connection between H. pylori and reflux symptoms is more complicated: in some cases, infection can increase acid secretion, whereas more severe gastritis and atrophy may decrease stomach acid, and in certain populations it is even inversely related to gastro-oesophageal reflux disease [3,4].

The symptoms associated with H. pylori may differ: in some cases people with H. pylori experience a burning in the upper abdomen, nausea, a feeling of fullness after eating only a small amount of food, bloating, belching, or pain similar to that of an ulcer and refer to it as heartburn. In other instances the problem is reflux resulting from dysfunction of the lower oesophageal sphincter, delayed gastric emptying, acid reflux and a hiatal hernia or increased abdominal pressure. The problem is that these symptoms can overlap.

Stomach acid and H. pylori

Depending on where the inflammation is most severe and on how long the infection has been going on, H. pylori can have different effects on the regulation of stomach acid. It can cause inflammation in the lower part of the stomach, leading to a decrease in somatostatin (the chemical messenger which is meant to prevent the overproduction of stomach acid), and as a result stomach acid levels rise. That is the reason why H. pylori has in the past been linked to a risk of duodenal ulcer in some patients [4].

Helicobacter pylori is a bacterium which produces urease. It takes urea, a waste product formed in the liver when your body breaks down proteins, and splits it into carbon dioxide and ammonium (NH4+), forming an "acid shield" that enables the bacteria to survive in the stomach's acidic environment. 

The bacteria generate a great deal of an enzyme known as urease, this enzyme breaking down the substances in the stomach into ammonia. Since ammonia is highly alkaline, it immediately neutralises the strong stomach acid that is nearby the bacteria, thus forming a safe and habitable area. As a result of this chemical reaction, the stomach's protective mucus layer is thinned out, which makes it much easier for the bacteria to swim through and attach directly to the stomach lining. Over a period of time, the process can lead to a serious and long-lasting reduction in the total amount of stomach acid because the infection destroys the cells responsible for producing it. The body's immune system responds to the bacteria, and this can cause chronic inflammation that shuts down the stomach's acid-producing cells by establishing a protective barrier. If the infection is left untreated for many years, the continual inflammation results in permanent damage to the tissue and scarring, completely destroying these cells. 

The absence of stomach acid eventually disrupts the normal process of digesting food, impairs the body's ability to absorb nutrients, and results in unwanted bacteria growing in excess within the digestive tract. That is exactly what happens when there is low stomach acid: it slows down digestion and might lead to bloating, changes in microbial growth, worries about nutrient absorption, or the feeling that food is remaining in the stomach for too long [3,10].

The problem is that both excessive and insufficient stomach acid can cause symptoms including a burning sensation, a feeling of pressure, or the reflux of acid. Excessive acid can irritate the stomach, while low stomach acid has an indirect effect because of poor digestion, fermentation, distension, belching, and sluggish gut motility, all of which can lead to increased pressure upwards and make acid reflux and heartburn worse. It doesn't follow that all people who have reflux have low stomach acid; rather, symptoms by themselves are not a reliable indicator.

Histamine, inflammation, acid secretion and symptoms

Histamine does have a valid function in the physiology of the stomach, not just in the context of allergic reactions. In the stomach, histamine released by enterochromaffin-like cells acts on parietal cells via H2 receptors to boost acid secretion. That is the reason why H2 receptor antihistamines (antagonists) such as famotidine, cimetidine, nizatidine and ranitidine are able to decrease acid levels and alleviate the symptoms of heartburn [5,6], and since anyone who knows my co-founder Dilly will stress and point out this fact, these H2 receptor antihistamines are designed to treat the symptoms of heartburn, I repeat, the symptoms.

H. pylori can disrupt all of that. On infection of the stomach, H. pylori causes inflammation. One would anticipate this to result in a huge increase in stomach acid since, by lowering somatostatin (the chemical messenger which stops the overproduction of stomach acid), the "brakes" are removed. But if the infection persists for a long time, it may cause the cells that produce stomach acid to shrink and degenerate. With fewer cells left to secrete stomach acid, the total amount of acid decreases, even though the body is still releasing high levels of the chemical signal (gastrin) in an attempt to boost acid production. Therefore, we cannot always state that H. pylori increases or decreases stomach acid, since it depends on the damage the bacterium has caused to the stomach lining.

Histamine intolerance and acid reflux

We also need to mention the role of histamine intolerance and acid reflux. Certain individuals experience flushing, headaches, nasal symptoms, itching, palpitations, or digestive discomfort following the consumption of histamine-containing foods such as fermented foods, wine, aged cheese, cured meats, or some leftovers. Although these symptoms can occur together with acid reflux, histamine intolerance is not the same as GERD or H. pylori gastritis.

In this scenario, I would look for patterns; if fermented foods, alcohol, or aged foods consistently cause symptoms, a brief, organised trial of cutting down on high-histamine foods might help determine whether histamine is causing the reflux. However, if symptoms include persistent pain in the middle of the abdomen, unexplained anaemia, black stools, vomiting, difficulty swallowing, or weight loss, a low-histamine diet may not be the most appropriate course to take.

H. pylori, Ammonium, and Heartburn

H. pylori is able to withstand stomach acid because of an enzyme called urease, which breaks down urea into ammonia and carbon dioxide. In the acidic environment of the stomach, H. pylori must use the ammonia to convert it into ammonium. For this conversion, the bacterium takes in a proton (H+) from the surrounding stomach acid, changing NH3 (ammonia) into NH4+ (ammonium); this action shields it from the stomach acid and stops it from being destroyed [2,7]. This is the reason why the urea breath test is often recommended and helps to explain why searches for ammonium and heartburn have become more common.

Ammonium can trigger reflux symptoms; urease activity and the production of ammonia/ammonium help H. pylori survive and may affect local pH. When the pH drops, digestion slows, so food stays in the stomach longer, which can cause acid reflux symptoms and slower digestion. Moreover, high levels of ammonium can also cause other symptoms such as confusion, fatigue, and tremors. [7,8].

How are H. pylori, GERD, histamine intolerance and low stomach acid to be told apart?

It's not that simple since these symptoms overlap. But you can work out what it might be by looking at when the symptoms occur, where they are felt, what triggers them, how they respond to medication, and the results of any tests, all of which can help to reduce the number of possible conditions. H. pylori gastritis usually results in discomfort in the upper abdomen, nausea, bloating, a feeling of fullness soon after eating, or pain similar to that of an ulcer; GERD on the other hand tends to cause a burning sensation behind the breastbone, sour reflux, irritation of the throat, or symptoms that appear when lying down. Likewise, low stomach acid and poor gut motility may lead to a sensation of heaviness after meals, bloating, belching, and food intolerance, but these symptoms are non-specific.

7 common patterns that could indicate what the underlying problem of your acid reflux could be:

1. A burning sensation behind the breastbone after eating or when lying down is more indicative of acid reflux, particularly when sour fluid is present or regurgitation occurs.
2. A gnawing stomach feeling, nausea, a quick onset of fullness, or ulcer-like discomfort may be associated with gastritis, peptic ulcers, and Helicobacter pylori, but the gnawing description fits Helicobacter particularly well.
3. Symptoms such as bloating, belching, distension, constipation, or inconsistent stools could be signs of dysmotility, SIBO-like patterns, food allergy, or medication side effects, particularly when taking PPIs and/or having low stomach acid.
4. If symptoms occur after eating fermented foods, wine, aged foods, or leftovers, this may indicate histamine sensitivity, especially if digestive symptoms aren't the only ones present (e.g., skin inflammation).
5. Acid reflux that occurs when bending, lifting, after large meals, or when lying down may indicate mechanical reflux, characterised by the lower oesophageal sphincter remaining open and allowing stomach acid to escape, or a hiatal hernia.
6. The relief of heartburn caused by antacids or by reducing acid production is generally associated with high stomach acid since antacids make the stomach acid more alkaline, but this can also cause heartburn because when the stomach acid is alkalinised the food takes longer to break down and be digested, and this may lead to mechanical reflux in which food pushes against the lower oesophageal sphincter and thus allows stomach acid to enter the oesophagus. 
7. A poor response to standard treatments for reflux, i.e., if your symptoms return after taking PPIs or antacids, and symptoms that recur after receiving triple or quadruple therapy for H. pylori. In these cases, discuss your diagnosis, compliance, medication timing, H. pylori testing, indications for endoscopy, and any factors related to gut motility with your practitioner.

The symptoms of H. Pylori frequently overlap with those of acid reflux and heartburn since all of these conditions may involve nausea, bloating, burping, abdominal pain, reflux symptoms, and a loss of appetite, just as these same symptoms can be found in functional dyspepsia, GERD, gallbladder disease, medication intolerance, SIBO, constipation, pregnancy, anxiety-related gut symptoms, or histamine symptoms.

7 Heartburn relief tips

While you work to find your root cause, I’ve put together some short-term heartburn relief tips I've found useful in practice. Remember to track your symptoms, when they occur, what you were doing, whether you were eating, and how you felt. This can help your practitioner evaluate your symptoms and find an individualised approach for you.

1. Meal timing: avoid large meals within two to three hours of lying down, especially if night-time reflux is a problem. I normally suggest that, after eating, you take a brisk 30-minute walk, as gentle motion stimulates your stomach and intestines, helping food move along faster and reducing bloating, gas, and acid reflux. 
2. Meal composition: An easier fix: look at your food triggers. Keeping a diary is important, as you might find certain carbohydrates, like wheat, are triggers. So, adjusting this in meals can provide short-term relief
3. Position: This can be awkward for the person sharing the bed, but instead of pillows or wedge pillows, some people report relief by raising the head of their bed by 6 to 8 inches, which uses gravity to keep stomach acid down and reduce nighttime acid reflux.
4. Count your chews: This is very much overlooked. Especially for many who work while eating, watch TV, or even chat. Without thinking, we chew less and swallow larger food pieces, so food is less broken down, and stomach acid has to work harder to process. Mastication (chewing) stimulates saliva secretion and swallowing, which helps clear acid from the oesophagus and reduce postprandial (after-meal) acid reflux. I suggest aiming for 20 chews!
5. Medication review: Long-term PPIs can change our acid profile; H2 antihistamines, NSAIDs, iron tablets, bisphosphonates, certain blood pressure drugs, and other medicines can worsen upper gastrointestinal symptoms. So, it’s important to talk with your practitioner about the medication; keeping that diary helps you see whether there are correlations, such as between medication timing and your symptoms.
6. Histamine triggers: Yeah, I’m going back to that diary, but if you see your symptoms match histamine-rich foods or even non-histamine-rich foods, consider removing these foods for a short period to see if it helps. However, work with your practitioner to ensure you are not missing out on any much-needed nutritional benefits.
7. Constipation and motility: Address fibre, stay hydrated (add an electrolyte), aim for better sleep, and add movement into your day, even a brisk walk. These are small changes, but they can considerably improve digestion through stool formation and gut motility, which can help lower heartburn. If you have poor gut motility, you may want to discuss adding magnesium with your practitioner.

The aim is not to suppress every symptom forever without asking why it exists. The aim is to reduce irritation while understanding your root cause.

Key takeaway

Helicobacter pylori, histamine, stomach acid, ammonium, low stomach acid and reflux may all be linked, since their symptoms overlap. It is still essential to clearly understand your symptoms, including when they occur and when and how they first began. Remember that H. pylori can affect acid regulation via gastrin, somatostatin, histamine signalling and urease-derived ammonium and that GERD can also result from anatomy, pressure, a hiatal hernia, delayed emptying and oesophageal sensitivity. Therefore, keep your notes, examine your triggers, and look for patterns, as this could help you work out what is actually going on and might point to the real cause of your acid reflux.

References

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