Why Your Endoscopy Was Normal But Your Reflux Isn't: H. pylori, Low Stomach Acid, and the GI-MAP

Quick answer: A normal endoscopy tells you that your esophagus does not have visible damage. It does not tell you why you still have a burning throat, a lump when you swallow, or pressure after every meal. Between half and three-quarters of people with reflux symptoms have a clean scope. The drivers a scope cannot see include how well your stomach is producing acid, whether H. pylori is living in your stomach lining and which strain it is, and how much gas your gut microbiome is producing under your diaphragm. A GI-MAP stool test reads several of those directly. Here is how I use it in my practice, and how to know if it is the right next step for you.

The Appointment You Have Probably Already Had

You waited weeks for the endoscopy. You did the prep, went under, woke up groggy, and a few days later got the note: "mild erythema, no erosions, no Barrett's, otherwise unremarkable." Your doctor increased your PPI or told you to keep taking it. Your throat still burns by mid-afternoon. You still feel the lump. You still get the pressure under your ribs an hour after dinner.

If that's you, I want to name something plainly. A normal scope is good news about one specific thing: your esophageal tissue is not visibly injured. It is not evidence that your symptoms are imagined, and it is not evidence that acid suppression is the whole answer. Roughly 50 to 75% of people with symptoms consistent with GERD have a completely normal endoscopy (Monés, 2005, Drugs, PMID 16335856, DOI). You are in the majority.

The reason is what a scope is built to find. Endoscopy looks for structural change you can see with a camera: erosions, strictures, Barrett's tissue, a hiatal hernia. It cannot measure how much acid your stomach makes. It cannot tell you what your microbiome is fermenting. It cannot tell you whether H. pylori is present unless a biopsy happens to be taken, and it cannot tell you which strain you carry even then.

Those are the questions I get asked to answer after the scope comes back clean. They are also the questions a functional stool test was built for.

The Too-Much-Acid Assumption

Most reflux care starts from one assumption: there is too much acid, so we suppress it. For a lot of people that is exactly right, at least in the short term. For a meaningful number of my clients, the picture is more complicated, and the complication is worth understanding before you decide what to do next.

Low stomach acid changes digestion in ways that can push reflux upward without any excess acid at all. Acid is your stomach's first line of defense against ingested microbes. When that barrier is weaker, bacteria that would normally be cleared have an easier time settling into the upper gut. Long-term acid suppression itself is a recognized driver of small intestinal bacterial overgrowth (Maslennikov et al., 2026, Medical Sciences, PMID 42346839, DOI). H. pylori is also associated with higher odds of SIBO: a 2023 systematic review and meta-analysis of 8 studies and 874 patients found people carrying H. pylori had about 1.8 times the odds of small intestinal bacterial overgrowth (Liao et al., 2023, BMC Microbiology, PMID 38053022, DOI).

Why does that matter for your throat? Because overgrowth ferments. Fermentation makes gas. Gas stretches the stomach and the small intestine, and a stretched stomach is one of the most reliable triggers of transient lower esophageal sphincter relaxations, the brief openings of the valve at the top of your stomach that let contents rise. In a randomized study of healthy volunteers, mechanically distending the esophagogastric junction increased the number of these relaxations after a meal from about 15 to about 22 (van Wijk et al., 2011, American Journal of Physiology: Gastrointestinal and Liver Physiology, n=10, PMID 21817061, DOI). Pressure opens the valve. That is the mechanism behind "I eat a normal meal and an hour later my throat is on fire," and it does not require high acid.

This is why suppressing acid harder sometimes does nothing for the pressure-driven part of reflux. The pressure is coming from below.

Where H. Pylori Fits, Honestly

H. pylori is a spiral-shaped bacterium that has adapted to live in the acid of your stomach. It survives by producing an enzyme called urease, which converts urea into ammonia and carbon dioxide, neutralizing the acid immediately around the bacterium so it can colonize the lining (Graham and Miftahussurur, 2018, Journal of Advanced Research, PMID 30094082, DOI). Roughly 43% of people worldwide carry it, based on a meta-analysis of 224 studies covering nearly 3 million individuals (Li et al., 2023, The Lancet Gastroenterology and Hepatology, PMID 37086739, DOI). Most carriers never know.

Here is where I want to be careful with you, because the internet has flattened this into "H. pylori causes reflux," and the research does not say that.

At the population level, H. pylori is actually inversely associated with GERD. A 2025 meta-analysis found carriers had lower odds of GERD than non-carriers (Zhou et al., 2025, BMC Gastroenterology, PMID 41299341, DOI). The reason is location. When H. pylori settles in the body of the stomach, it damages acid-producing tissue and lowers acid output over time, which can protect against erosive esophagitis. When it settles in the lower stomach, acid output tends to rise, and clearing it often improves existing reflux esophagitis (Yucel, 2018, Esophagus, PMID 30151653, DOI).

So the honest clinical picture is this. H. pylori can raise your acid or lower it depending on where it lives. It drives chronic gastritis and dyspepsia, which produce the upper-belly burning, early fullness, and nausea that many people describe as "reflux." It is associated with more bacterial overgrowth downstream, which feeds the pressure mechanism above. And clearing it can occasionally unmask reflux rather than resolve it, which is a reason to know what you carry before anything is treated. It is never a reason to leave it alone: H. pylori is a recognized risk factor for gastric cancer, and treatment decisions belong with you and your physician.

None of that shows up on a standard endoscopy report.

What I Actually Look At On A GI-MAP

The GI-MAP is a stool test that uses quantitative PCR to measure the DNA of specific organisms and markers. It sits alongside endoscopy rather than replacing it, and it answers several of the "why" questions a clean scope leaves open. Here is what I teach my clients to look at, in the order I read it.

• H. pylori and its virulence factors. The panel reports whether H. pylori DNA is present and at what level, and it reports several virulence genes, including cagA and vacA. Strains carrying these genes are associated with more aggressive gastric inflammation than strains without them (Wang, 2014, World Journal of Gastroenterology, PMID 25132753, DOI). A quiet carrier and someone with a cagA-positive strain are two different conversations, and the plan is different for each.

• Commensal and opportunistic bacteria. This section shows the balance of your normal residents alongside organisms like Streptococcus, Staphylococcus, and methane-producing archaea. Overgrowth in the upper gut is where fermentation, bloating, and that upward pressure on the LES come from. This is the section that most often explains "I eat clean and I still get pressure."

• Pancreatic elastase-1. This marker reflects how much digestive enzyme your pancreas is releasing. Low output is more common than people expect: population studies estimate pancreatic exocrine insufficiency in 11 to 21% of unselected gastroenterology patients, and it frequently hides inside IBS-type symptoms (Cotton et al., 2026, Current Opinion in Gastroenterology, PMID 41782402, DOI). Incomplete digestion means more undigested food reaches bacteria that ferment it. More fermentation, more gas, more pressure.

• Secretory IgA. This is the antibody your gut lining secretes as its first immune layer. I read it as a marker of how well-defended and well-resourced the mucosal barrier is. A very low or very high value changes how gently we start.

• Inflammation and permeability markers. Calprotectin and zonulin round out the picture and tell me how reactive the lining is before we add anything to it.

Read together, these markers give you a map of the digestive terrain underneath your reflux. That is different from a positive or negative flag. In my 1:1 practice, when we review a client's GI-MAP inside The Microbiome Map, the question is bigger than "is H. pylori there." Is it a strain that matters, what is the overgrowth picture below it, is digestion strong enough to support the plan, and what does the lining need before we ask it to tolerate anything new.

What We Do With What We Find

Let me show you what this looks like in practice. The details below are a composite drawn from the pattern I see most often, with nothing that identifies any one person.

She is in her late thirties. Two years of throat burning, a lump when she swallows, and pressure under her ribs after dinner. Her endoscopy came back with "mild erythema, otherwise unremarkable." She has been on a PPI for eighteen months and has cut her diet down to about a dozen foods. Her GI doctor's last suggestion was to double the dose.

Her GI-MAP told a different story. H. pylori was present at a high level, and the cagA virulence gene was positive. Her commensal bacteria were low across the board, and Streptococcus and methane-producing archaea were both elevated. Her pancreatic elastase-1 sat in the low range, so a good portion of what she ate was reaching those bacteria undigested. Secretory IgA was low, which told me her lining was under-resourced before we asked it to tolerate anything new.

So we did not start with antimicrobials, and we did not start with betaine HCl. We spent the first four weeks on the lining and on digestion: slippery elm and DGL for mucosal soothing, the LES Lock after every meal, the 3-Hour Buffer, and a gentle expansion of cooked, low-fermentation vegetables to start feeding the commensals back. Her pressure after dinner dropped first. Weeks five through eight, with her physician's input on the H. pylori result, we layered in targeted botanical and dietary support for overgrowth while keeping the lining protocol in place. The throat burning followed. By week twelve she was eating from a list three times longer than the one she came in with, and her follow-up conversation with her GI was about tapering, with a real rationale behind it instead of a hope.

That sequence is the whole point. The order matters more than the ingredients. Restriction alone doesn't rebuild the mechanisms that are failing. It doesn't restore digestive output. It doesn't change what is fermenting under your diaphragm. It doesn't soothe a lining that is already irritated. So we build, and we build in sequence: support digestion and the mucosal barrier first, then address overgrowth and H. pylori with your physician's input where appropriate, then reintroduce and expand your food world as the pressure comes down.

Two cautions I give every client, because I see the damage when they are skipped. First, a GI-MAP report often arrives with a standardized supplement printout attached. That printout does not know your history, your medications, or the state of your lining. Second, the two most common self-directed moves I see after a positive H. pylori result, betaine HCl for "low acid" and a stack of botanical antimicrobials, are exactly the two moves that can inflame irritated tissue if the barrier has not been supported first. Interpreting this panel requires clinical context. You deserve support that actually explains why.

Still symptomatic after a normal scope and a PPI? This is the exact situation The Microbiome Map was built for. It is an application-only program with our expert team of reflux Dietitians: the GI-MAP stool test shipped to your door, a full clinical interpretation of every marker (not a software summary), a 60-minute roadmap session to walk through your results, a written protocol phased over about 12 weeks, 30 days of messaging support, and a follow-up to adjust what needs adjusting. The full program is $1,150. I read every application myself, and if a GI-MAP is not your best next step, I will tell you that before you spend a dollar. Apply for The Microbiome Map

The Question to Bring to Your Next Appointment

The question isn't whether your scope was normal. It was, and that is worth being glad about. The question is: what is driving symptoms that a scope was never designed to see, and are you ready to look?

Small hinges swing big doors. The clean scope already ruled out the scariest possibilities. Now you get to find the actual drivers.

Related reading on mollypelletier.com:

• H. pylori and Acid Reflux: The Stomach Bacteria Most People Never Get Tested For

• Why You're Always Clearing Your Throat (Meet Pepsin, the Enzyme Behind Silent Reflux)

If you're ready for a map instead of another guess, applications for The Microbiome Map with our expert team of reflux Dietitians are open at mollypelletier.com/gi-map-analysis/application.

With love, Molly Pelletier, MS, RD