Some foods trigger heartburn, or acid reflux, in many people, including fatty foods (especially as part of a large meal), chocolate, black pepper, raw onions and garlic. Other trigger foods include citrus fruits and juices, caffeinated beverages, tomatoes and peppermint. Different people respond differently to various foods, says WebMD.
Acid reflux strikes most often after a big meal. When the stomach contains much food, it stretches, leading to a "stuffed" feeling. The stretching applies pressure to the LES, a muscular ring that normally prevents stomach acid from heading the wrong way. This pressure allows acid to go back into the esophagus, causing acid reflux, according to WebMD.
It is best for people who suffer from acid reflux regularly to avoid fatty foods, as these remain in the stomach longer than other foods. The stomach sends out more acid in response in an attempt to spur digestion, but the end result is irritation throughout the digestive system. Also, greasy and fatty foods cause the LES to relax and weaken. This means that the stomach has more acid in it, and the contents are more likely to move back up into the esophagus, notes WebMD.
The exact list of foods that causes acid reflux differs from one person to the next. There is no reason to avoid foods that do not cause problems. Behavioral changes, such as eating smaller meals and waiting at least two hours after eating to go to bed, allow the digestive process to be less stressful and give the stomach time to deal with food before a person lies down for the night, states WebMD.