Capsaicin, the pungent ingredient of chili, has a gastroprotective effect against experimental gastric mucosal injury in animals. Such an effect has not, however, been documented in humans to date. Eighteen healthy volunteers with normal index endoscopies underwent two studies four weeks apart. Each subject took 20 g chili orally with 200 ml water in one study and 200 ml water in another study. In each case this was followed half an hour later by 600 mg aspirin BP with 200 ml water. Endoscopy was repeated 6 hr later. Gastroduodenal mucosal damage was assessed by a previously validated scoring system. The median gastric injury score after chili was 1.5 compared to 4 in the control group (P < 0.05), demonstrating a gastroprotective effect of chili in human subjects.