Heartburn happens when the excessive food and liquid in the stomach churns up stomach acid which spills up into the esophagus and irritates the lining of the upper stomach and esophagus, as shown in this picture. 
Heartburn is often experienced as pain, a burning sensation in the stomach or chest, abdominal bloating, gurgling, distention, or belching.
Let’s jump right into what Chinese medicine says about heartburn, or overall indigestion.Chinese medicine says there are three main causes of indigestion:
- Poor diet damages the spleen-pancreas-stomach network.
- Emotional turmoil stressed the liver-gallbladder network, slows down the digestive process, and potentially cause hiatal hernia by pulling the stomach upward into the diaphragm.
- Pathogens in a post-nasal mucus drip or food-borne microbes can invade the stomach, causing upheaval.
In a nutshell, Chinese medicine views heartburn is not just a digestive malfunction, rather it is a mixed bag of poor diet, emotional/psychological issues, and immune functions relating to sinuses. I can vouch for this theory as almost all of the heartburn patients I have treated demonstrated stress/anxiety syndromes, chronic mucus drips, and relatively poor diet patterns.