What causes bloating after eating certain foods?

Bloating after eating is primarily caused by gas production in the digestive tract. When you eat foods high in fermentable carbohydrates, like beans, lentils, cruciferous vegetables, onions, and dairy products, gut bacteria break them down through fermentation, releasing hydrogen, methane, and carbon dioxide gas. This gas accumulates and stretches the intestines, causing that uncomfortable full, tight feeling. Other contributing factors include swallowing air while eating, eating too quickly, food intolerances like lactose or gluten sensitivity, and slow gastric emptying. People with irritable bowel syndrome are often more sensitive to normal amounts of intestinal gas. Carbonated drinks add gas directly to the gut, and high-sodium foods cause water retention, which can mimic or worsen bloating.