Gastritis is inflammation of the gastric mucosa (stomach lining). Acute gastritis typically develops suddenly — from alcohol, NSAIDs (ibuprofen, aspirin), stress, or infection. Chronic gastritis develops gradually; Helicobacter pylori (H. pylori) infection is the leading cause worldwide and is treated with antibiotics.
Symptoms include upper abdominal discomfort, nausea, bloating, and early satiety — though many people with chronic gastritis have no symptoms at all.
Dietary triggers vary considerably between individuals. Alcohol, spicy food, coffee, and highly acidic foods are commonly reported irritants, but the evidence that any specific food causes gastritis (as opposed to transiently worsening symptoms) is limited. The priority is treating the underlying cause.
If H. pylori is confirmed, antibiotic eradication therapy is the treatment — not dietary restriction alone. For NSAID-related gastritis, the medication is usually changed or a stomach-protecting drug (PPI) added. Chronic atrophic gastritis can impair B12 absorption (intrinsic factor loss), increasing the risk of B12 deficiency.
Do not self-manage persistent upper GI symptoms with diet alone; get an appropriate clinical assessment first.