Which of the following is NOT a main cause of Peptic Ulcer Disease?

Peptic Ulcer Disease (PUD) is primarily caused by an imbalance between the aggressive factors that damage the gastric mucosa and the defensive factors that protect it. The most well-established causes include infection with Helicobacter pylori, the chronic use of nonsteroidal anti-inflammatory drugs (NSAIDs), and smoking.

Helicobacter pylori is a bacterium that colonizes the stomach lining and is a major contributor to ulcer formation. It causes inflammation and leads to erosion of the mucosal barrier.

Chronic NSAID use is another significant risk factor for developing PUD. NSAIDs inhibit prostaglandin synthesis, which is crucial for maintaining the gastric mucosa's protective barrier, thereby increasing the risk of ulceration.

Smoking has a well-documented association with peptic ulcers; it not only increases acid secretion but also impairs healing of existing ulcers, making them more difficult to treat.

Alcohol, while it can irritate the stomach lining, is not considered a primary cause of peptic ulcers. Its role in ulcer formation is more complex and less direct than the other factors mentioned. While excessive alcohol use can exacerbate ulcer symptoms and potentially worsen existing ulcers, it is not a primary cause like the other three factors. This is why alcohol