French fries, often high in fat, can slow stomach emptying. This frequently leads to bloating, indigestion, and pain, which is detrimental for individuals with stomach ulcers.

Citrus fruits like oranges and mandarins are rich in acid, which can irritate the stomach and intensify feelings of pain and burning. While patients do not need to avoid them entirely, they should consume them in moderation (about one to two fruits per week) and avoid eating them on an empty stomach. Beyond oranges and mandarins, patients should also limit other sour fruits such as hog plums, tamarind, and pomelo.

Spicy seasonings such as chili, mustard, and pepper can irritate the stomach, increasing sensations of pain and burning. Capsaicin, the active compound in chili, makes the stomach lining more susceptible to irritation, thereby worsening ulcer symptoms.

Pizza, rich in fat and refined carbohydrates, can irritate the stomach, heighten inflammation, and make the stomach lining more vulnerable to damage. For individuals infected with H. pylori bacteria, these foods can exacerbate the condition and increase the risk of stomach ulcers.

Dried squid and dried fish are heavily salted for preservation and to maintain their distinct flavor. Salty foods can weaken the stomach's protective lining, making the stomach more sensitive and allowing lesions to progress easily, especially in individuals infected with H. pylori. Patients with stomach ulcers should limit heavily salted or marinated dishes. When consuming pickled vegetables like pickled cucumbers or salted eggplant, opt for low-salt varieties.