Heartburn is not too much.
It is a not-enough.

What heartburn really is.

Heartburn is not a diagnosis. It is a symptom. A burning pain that arises because stomach contents move upward into the oesophagus, where they do not belong. The mucosa of the oesophagus is not made for acid. The mucosa of the stomach is. That is the difference.

The old story says: your stomach makes too much acid, so we block the acid. This story is simple on one side and sometimes wrong on the other. It ignores that there are many ways for acid to end up where it should not be. And one of the most common is the opposite: you have too little acid, your meal ferments, pressure builds, and the pressure pushes everything upward.

Several floors, one story.

In functional medicine and clinical psychoneuroimmunology, we look at heartburn through four lenses: the nervous system, the immune system, metabolism, and the hormonal system. They are not boxes. They are floors of a house in which your stomach lives.

Two stomachs that look the same.

The most important thing you can learn about your stomach is how to tell its variants apart. Two people can both have heartburn and need exactly the opposite of each other. If you skip this distinction, you treat in the dark.

What mainstream gastro rarely looks at.

This is the part where functional medicine parts ways with classic mainstream care. Not because mainstream is wrong. But because it rarely looks exactly here, where the pain often has its real root.

1. Parasites and fungi that quietly turn your acid down

Parasitic stomach worms can damage parietal cells directly. In animal models this leads to hypergastrinaemia, acid suppression, and a loss of acid-producing cells. Fungi like Candida albicans can also colonize the stomach, especially when the pH has already been raised by long-term acid blockers. There are documented cases of gastric ulcers that did not heal for months despite pantoprazole and only resolved after antifungal therapy with fluconazole.

2. Mycotoxins from mould: the hidden irritant

Mould is not only a problem of damp walls. Aflatoxins in poorly stored grain, ochratoxins in coffee, patulin in apple juice, candidalysin from your own gut fungus, all of these can inflame the gastric mucosa and shift the microbiome. Mycotoxins can disrupt the mechanical and immunological barrier of the mucosa, inhibit protein synthesis, and drive pro-inflammatory cytokines such as interleukin 1-beta and interleukin 17.

3. Autoimmune atrophic gastritis: the underdiagnosed silence

In autoimmune atrophic gastritis, your own immune system attacks the parietal cells that produce stomach acid. Acid production drops gradually, B12 drops with it, iron is no longer properly unlocked. These patients are often women, often over 50, often with other autoimmune conditions such as Hashimoto. They rarely come to me saying "heartburn", they come with fatigue, hair loss, burning tongue, tingling feet. Two blood tests can support the suspicion: parietal cell antibodies and intrinsic factor antibodies.

4. Stress and the cortisol carousel

The evidence here is stronger than I myself long thought. Chronic stress can drive cortisol up, cortisol relaxes the lower oesophageal sphincter, increases visceral sensitivity of the oesophagus, and weakens the mucosal barrier. A growing number of reviews describe the brain-gut axis as a central engine of refractory reflux symptoms. If your heartburn reliably gets worse in stressful weeks, that is not a psychosomatic fantasy. That is endocrinology.

Carnivore, vegan, or just clear?

I get this question often, and it is smarter than it sounds. There are patients who lose their years of heartburn on a carnivore diet. There are patients who lose their years of heartburn on a vegan diet. Both are right. Both remove the same thing.

For the patient who comes in with hypochlorhydria and chronic gastric slowness, a protein-heavy or temporarily carnivore approach can be a real therapeutic lift. It activates the natural acid response, removes upper-abdominal fermentation, takes the constant sugar load off the microbiome, and gives the stomach a clear meal that can be answered with acid. Important: an adaptation phase of two to four weeks, good chewing, calm eating, and if necessary external acid support until the stomach pedals on its own again.

Why PPIs often cost you more than they give.

PPIs, pantoprazole, omeprazole, and their relatives, are among the most prescribed drug classes in the Western world. In the right indications, like acute erosive reflux oesophagitis, the Helicobacter regimen, or ulcer prophylaxis under pain medication, they are a medical achievement. But they are also among the most prescribed long-term medications for a problem they do not solve on the long run, and often make worse.

The official AGA Clinical Practice Update from 2022 was the first to explicitly use the term "deprescribing" for PPIs. It is no longer awkward to take a patient off the pill. It is medical work.

What you can start today.

You do not need to wait for the big diagnostic marathon. There are levers you can pull today, and most of them cost nothing.

What your stomach really needs.

Your stomach has never betrayed you. It has been sending you a message the whole time, in a language you were never taught. Burning does not mean "too much". Burning means: "something is not where it should be." Sometimes it is the acid. Sometimes it is the calm before the meal. Sometimes it is an undetected parasite, a quietly working fungus, a flat in which mould lives in the wall, an autoimmune reaction, a ten-year stress phase, or a meal that needs twenty minutes but only got two.

You are not too complicated. You are not too sensitive. Your stomach is an electrochemical wonder, and it deserves the right to work the way it was evolutionarily meant to.