Acid reflux is a condition that causes a burning feeling in the abdomen and chest, known as heartburn. The condition also causes the regurgitation of a bitter acid into the mouth and can be accompanied by burping, bloating, nausea, hiccups and even weight loss. This is a condition most often caused by a hiatal hernia, which occurs when the upper region of the stomach, along with the lower esophageal sphincter, move.
Both the LES and upper section of the stomach will go above the diaphragm muscle, which separates the chest and stomach, and stops stomach acid from moving up to the esophagus. A person suffering from a hiatal hernia will experience acid reflux, though people without such a hernia can also experience reflux. The condition can be caused by obesity, or by eating particularly large portions of food, lying down after eating or eating specific foods like garlic, carbonated drinks, tomatoes, and spicy foods.