Not Everything That Burns Is Acid Reflux

When people experience a burning sensation in the stomach after eating, the default assumption is usually gastro-oesophageal reflux disease (GERD) or excess stomach acid. This assumption drives millions of people to reach for antacids and proton pump inhibitors. But burning epigastric pain has a wider differential diagnosis than most people realise, and misidentifying the cause can lead to years of treatment that does not address the underlying problem and may even make it worse.

The location, timing, and associated symptoms of the burning sensation provide important clues about its origin. Burning centred behind the breastbone that worsens when lying down is classic reflux. Burning in the upper central abdomen (epigastrium) that occurs during or shortly after eating has a broader set of potential causes.

Gastritis: Inflammation of the Stomach Lining

Gastritis is inflammation of the stomach mucosa and is one of the most common causes of burning stomach pain. Unlike reflux, which involves acid moving upward into the oesophagus, gastritis pain comes from the inflamed stomach lining itself being irritated by acid and food. The burning is typically felt in the upper abdomen, may be relieved briefly by eating (as food buffers the acid), and then worsens again as digestion progresses.

Common causes of gastritis include:

  • H. pylori infection — the most common cause worldwide, responsible for the majority of chronic gastritis cases
  • NSAID use — ibuprofen, aspirin, and naproxen directly damage the protective mucus layer of the stomach
  • Alcohol — irritates and inflames the gastric mucosa, particularly with regular or heavy consumption
  • Autoimmune gastritis — the immune system attacks parietal cells, eventually reducing acid production and causing B12 deficiency
  • Bile reflux — bile flowing backward from the duodenum into the stomach causes a distinct burning that does not respond to acid-suppressing medication
If burning stomach pain does not improve with acid-suppressing medication, bile reflux or a non-acid cause should be considered. Continuing to escalate acid suppression when the diagnosis is wrong delays effective treatment and may cause complications from long-term acid suppression.

Peptic Ulcer Disease

Peptic ulcers are open sores in the lining of the stomach (gastric ulcers) or duodenum (duodenal ulcers). They cause a burning, gnawing pain that may be worse with eating (gastric ulcers) or relieved by eating and worse when the stomach is empty (duodenal ulcers). The distinction matters because the two types have different relationships to food timing.

The vast majority of peptic ulcers are caused by H. pylori infection or NSAID use. The burning pain from an ulcer is often more intense and localised than the diffuse discomfort of gastritis and may wake patients from sleep in the early morning hours.

Functional Dyspepsia

Functional dyspepsia produces burning epigastric pain that is indistinguishable from gastritis or ulcer pain, but endoscopy reveals no structural abnormality. The burning is caused by visceral hypersensitivity, where the stomach nerves over-respond to normal stimuli including acid, distension, and food contact. This condition is extremely common, affecting up to 20 percent of the population, and is a frequent source of frustration when repeated investigations fail to identify a structural cause.

Low Stomach Acid Mimicking High Acid

Paradoxically, low stomach acid (hypochlorhydria) can produce burning sensations that feel identical to excess acid. When acid production is insufficient, food ferments in the stomach, producing organic acids and gas that irritate the stomach lining. The burning sensation drives people to take antacids, which further reduce acid production and worsen the underlying problem. Clues that low acid may be the issue include bloating immediately after eating, excessive belching, feeling food sitting in the stomach for hours, and nutrient deficiencies despite adequate intake.

Less Common Causes

  • Eosinophilic gastritis — allergic inflammation of the stomach wall
  • Gastric cancer — persistent burning pain with weight loss and appetite changes in adults over 55 warrants endoscopic investigation
  • Zollinger-Ellison syndrome — a rare tumour that produces excessive gastrin, causing severe acid overproduction and recurrent ulcers
  • Mesenteric ischaemia — reduced blood flow to the gut after eating, typically in elderly patients with cardiovascular disease

Getting the Right Diagnosis

The critical first step is H. pylori testing, which can be done via breath test, stool antigen, or blood antibody test. If positive, eradication therapy often resolves the burning. If negative, an upper endoscopy can visualise the stomach and duodenal lining directly, identify gastritis, ulcers, or other pathology, and take biopsies if needed.

  • Keep a detailed food and symptom diary to identify timing patterns and triggers
  • Note whether the burning is worse on an empty stomach or after eating
  • Document whether antacids provide relief (suggesting acid-related) or make no difference (suggesting a non-acid cause)
  • Record any associated symptoms: nausea, weight loss, vomiting, black stools

GutIQ helps you systematically track the relationship between meals, symptoms, and timing to identify patterns that guide your healthcare provider toward the correct diagnosis rather than defaulting to acid suppression therapy.