Some acid-producing foods are chocolate, high-fat dairy products, high-fat meats and any fried foods. Tangy citrus fruits and tomatoes are acidic in themselves, garlic, onions, spicy foods, and cheese can promote the production of stomach acid, and peppermint can cause acid reflux.
Tangy fruits, such as grapefruit, oranges and tomatoes, are highly acidic. When they are consumed, especially on an empty stomach, they can cause heartburn. Peppermint causes indigestion because its consumption relaxes the sphincter muscle that sits at the entrance to the stomach from the esophagus, causing stomach acids to flow back into the esophagus.
Foods high in fat, such as cheese, nuts, avocados and steak, can also be major triggers of heartburn. Fat slows down the emptying of the stomach, increasing chances of a distended stomach, which puts pressure on the esophageal sphincter, making heartburn more likely. Eating these high-fat foods at the beginning of a meal, rather than towards the end, can lessen the probability of hyperacidity. Chocolate seems to cause more cases of acid reflux than any other food. It contains caffeine, which triggers indigestion, and is very high in fat. Deep-fried foods are also high in fat and should be avoided in people who experience acid reflux.