Gastritis

References & Evidence Notes

Each numbered entry below is either a source you can follow or a note setting out what the evidence does and does not support. Both are numbered together so the markers in the text line up.

Last reviewed October 20, 2026. Supplement entries are cross-checked against the NIH National Center for Complementary and Integrative Health and the Linus Pauling Institute Micronutrient Information Center.⁸ The single most useful thing on this page is this: if you have persistent indigestion, get tested for Helicobacter pylori. It is a treatable bacterial infection, it is the leading modifiable cause of stomach cancer, and clearing it removes that risk factor. Eradication means a course of antibiotics with acid suppression, prescribed and confirmed afterward with a test of cure. Nothing on this page eradicates it, and the supplements here earn their place by supporting the stomach lining alongside that treatment, never in place of it. Some symptoms mean endoscopy rather than any diet: vomiting blood or coffee-ground material, black tarry stools, difficulty swallowing, unintentional weight loss, persistent vomiting, anemia or new indigestion starting in later life. Those need assessment now, not a trial of something gentle first.

1. On H. pylori and cancer risk: the International Agency for Research on Cancer classifies Helicobacter pylori as a Group 1 carcinogen, the same certainty category as tobacco smoke. This is a statement about how confident we are that it causes cancer, not about how large the risk is for any individual: most infected people never develop gastric cancer. Infection drives a progression from chronic gastritis through atrophy and intestinal metaplasia, and eradication reduces subsequent gastric cancer risk, with greater benefit the earlier in that sequence it happens. ↩
2. On testing: urea breath test and stool antigen test both detect active infection and are used to confirm eradication. Both require stopping proton pump inhibitors for around two weeks and antibiotics for four beforehand, or they produce false negatives. Serology detects past exposure, cannot distinguish active from resolved infection and is not used to confirm cure. A test of cure after treatment is standard and frequently skipped, which matters because resistance means a meaningful proportion of first-line courses fail. ↩
3. On endoscopy and alarm features: hematemesis or coffee-ground vomiting, melena, dysphagia, unintentional weight loss, persistent vomiting, iron-deficiency anemia, a palpable mass or new-onset dyspepsia in an older adult all warrant endoscopy rather than empirical treatment. Age thresholds differ between guidelines, with current US guidance commonly citing 60. Endoscopy also identifies atrophic gastritis, intestinal metaplasia and dysplasia, which change follow-up. ↩
4. On mastic gum, stated plainly because the stakes are unusual here. Mastic resin has demonstrable activity against H. pylori in laboratory conditions. Translating that into eradication in people has not succeeded. A controlled study by Bebb and colleagues found that mastic gum did not eradicate H. pylori in any participant (J Antimicrob Chemother. 2003;52(3):522-⁠523. PubMed 12888582). A later small study reported eradication in roughly a third of patients on monotherapy at best, well below the rates expected of antibiotic regimens. Claims circulating online of 70 to 80% eradication are not supported by the trial literature. Mastic may still be reasonable for symptom relief and mucosal support, and it is retained here on that basis. It is not an alternative to eradication therapy, and treating it as one leaves a Group 1 carcinogen in place. ↩ ↩
5. On sulforaphane and manuka honey: broccoli sprout sulforaphane has human data showing reduced markers of H. pylori colonization and gastric inflammation during intake, with effects that diminish after stopping, and it does not clear the infection. Manuka honey inhibits H. pylori in laboratory culture; there is no clinical trial evidence that eating it eradicates the organism. Both are reasonable foods. Neither is treatment. ↩ ↩
6. On the other causes: NSAIDs and aspirin cause gastric mucosal injury by inhibiting prostaglandin-mediated protection, and this is dose-related and often silent until bleeding occurs. Alcohol, bile reflux, severe physiological stress and radiation are other recognized causes. Autoimmune gastritis destroys parietal cells, producing achlorhydria and loss of intrinsic factor, and therefore vitamin B12 deficiency and pernicious anemia; it also carries increased risk of gastric neuroendocrine tumors and adenocarcinoma, both quantified in a meta-analysis of follow-up studies, PubMed 41398405, so it warrants surveillance and B12 replacement rather than dietary management. ↩
7. On acid suppression and nutrition: long-term proton pump inhibitor use is associated with reduced absorption of vitamin B12, magnesium, iron and calcium, and with an increased risk of enteric infection including C. difficile. These are reasons for periodic review of whether the drug is still needed and for monitoring, not reasons to stop a PPI that is treating something; gastroenterology guidance sets out how that review is done, PubMed 35183361. Stopping abruptly after prolonged use causes rebound acid hypersecretion, which is well described and is why discontinuation is tapered rather than sudden, PubMed 38791497. ↩
8. National Center for Complementary and Integrative Health (NIH), nccih.nih.gov, and the Linus Pauling Institute Micronutrient Information Center, lpi.oregonstate.edu/mic. ↩
9. On first-line H. pylori treatment: the American College of Gastroenterology's 2024 guideline recommends optimized bismuth quadruple therapy for 14 days for treatment-naive patients, PubMed 39626064, as summarized by the college itself, ACG summary, 2024. ↩
10. On eradication rates: a 2011 European randomized trial in 440 adults found H. pylori was eradicated in 80% of those given 10 days of bismuth quadruple therapy against 55% of those given 7 days of clarithromycin triple therapy, by intention to treat, PubMed 21345487. ↩
11. On proton pump inhibitors and fracture: a 2011 meta-analysis of 10 observational studies with 223,210 fracture cases found a modest association between PPI use and hip and vertebral fractures, odds ratios 1.25 and 1.50. It noted that observational studies cannot show whether the link is causal, PubMed 21483462. ↩
12. On how common H. pylori is: a meta-analysis of 184 studies from 62 countries estimated that about 4.4 billion people carried H. pylori in 2015, more than half the world's population, from 24.4% in Oceania to 70.1% in Africa, PubMed 28456631. ↩
13. On the size of the cancer risk: a combined analysis of 12 studies nested in prospective cohorts, with 1,228 gastric cancer cases, put the relative risk of non-cardia gastric cancer with H. pylori infection at 5.9, and found no increase in cancer of the gastric cardia, PubMed 11511555. ↩
14. On eradication and cancer prevention: a meta-analysis of seven randomized trials in 8,323 healthy H. pylori-positive adults found eradication therapy reduced later gastric cancer incidence (relative risk 0.54) and gastric cancer deaths (relative risk 0.61), with moderate evidence drawn mainly from East Asian countries, PubMed 32205420. ↩
15. On the causes: the National Institute of Diabetes and Digestive and Kidney Diseases lists H. pylori infection, long-term NSAID use, alcohol, bile reflux (most often after stomach surgery), autoimmune attack and severe physical illness as the common causes of gastritis and gastropathy, NIDDK. ↩
16. On treatment and urgent symptoms: the NHS advises emergency care for vomiting blood or coffee-ground vomit, black sticky stools, or sudden severe abdominal or chest pain, and an urgent appointment for weight loss without trying, difficulty swallowing, repeated vomiting or a lump in the abdomen, NHS. ↩
17. On retreatment: the 2024 American College of Gastroenterology guideline calls for a test of cure after treatment in everyone, and sets out which regimens to use when infection persists after a first course, PubMed 39626064. ↩
18. On the antibody tests: US gastroenterology guidance advises considering parietal cell and intrinsic factor antibodies to assist the diagnosis when biopsies are compatible with autoimmune gastritis, PubMed 34454714; parietal cell antibodies are found in 85 to 90% of people with pernicious anemia, but they also occur in other diseases, so their presence alone is not enough for the diagnosis, PubMed 26918709. ↩
19. On green tea: epigallocatechin gallate, the most active of six tea catechins tested, inhibited H. pylori in the laboratory and cleared it in a minority of infected gerbils; this is laboratory and animal work, not evidence that drinking tea clears the infection in people, PubMed 10390246. ↩
20. On S. boulardii: a meta-analysis of 11 randomized trials with 2,200 participants found that adding S. boulardii to a standard H. pylori regimen modestly raised the eradication rate, which still fell short of the desired level, and reduced treatment side effects, particularly diarrhea; it was studied only as an addition to antibiotics, PubMed 25898944. ↩
21. On low-dose aspirin: the NHS advises people who regularly take low-dose aspirin to keep taking it unless they are advised to stop, and lists stomach ulcers and bleeding among its serious side effects, NHS. ↩
22. On finishing H. pylori treatment: the NIDDK advises taking every dose exactly as prescribed, because if the medicine is stopped early, some bacteria may survive and become resistant to antibiotics, NIDDK, treatment for peptic ulcers. ↩